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PHYSIOLOGY 103 Classes 1-5
Summary
Chemical Level - atoms, molecules, organelles
Cellular Level – muscle cells, nerve cells, adipose cells, epithelial cells
Tissue Level - epithelium, muscle, connective, nervous
Organ Level - heart, lungs, stomach
Organ System – cardiovascular, digestive, respiratory
Organism Level
Necessary Functions for Life
1. Maintain boundaries
2. Movement
3. Responsiveness/Irritability
4. Digestion
5. Metabolism
6. Excretion
7. Reproduction
8. Growth
Survival Needs
1. Nutrients - carbohydrates, proteins, fats, minerals and vitamins
2. Oxygen
3. Water
4. Normal Body Temperature
5. Atmospheric Pressure
Homeostasis
 homeostasis = the body’s ability to maintain its relatively stable internal conditions
even though the outside world changes constantly
Negative Feedback
Positive Feedback
Basic Chemistry – atoms, ionic and covalent bonds
explains how the body is made of C, H, O, Na, Cl,
Basic Biochemistry – organic and inorganic makeup of the body
basic understanding of what the body is made of
Inorganic compounds
A. Water
Functions of water:
1. Formation of Solutions
2. Reactivity
3. Temperature Regulation
4. Cushioning
5. Lubrication
B. Salts
Functions of salts:
ionic compounds that carry an electric current in water…..electrolytes…when forming
their ionic bond, they became charged, when they split in water that negative or positive
ion exerts a pull on other positive or negative ions which creates movement of ions,
creating an electric current…nerve impulse transmission and muscle contraction depend
on the electrolyte properties
C. Acids and Bases
Functions of acids and bases:
chemicals used for various processes in the body…ex HCl…acid needed to digest food H
other acids and bases are needed to keep the body under control in disease states..body
can become acidic or basic and we need to correct it
Organic Compounds
A. Carbohydrates – contain carbon, hydrogen and oxygen
Functions of CHO: (Monosaccharides, Disaccharides, Polysaccharides)
great source of energy and storage
B. Lipids - contain carbon, hydrogen and oxygen, some have phosphorous
Functions of lipids: (triglycerides, phospholipids,steroids)
the most efficient and compact form of stored energy (triglycerides)
insulate deeper tissues from heat loss (triglycerides)
protect deep tissues from mechanical trauma (triglycerides)
important in building cell membranes (phospholipids)
found in cell membranes, in vitamin D, hormones, bile salts(cholesterol/steroids)
C. Proteins - contain carbon, oxygen, hydrogen and nitrogen
Functions of proteins: (amino acids)
basic structural material of the body
mechanical support, tensile strength (fibrous) ex. collagen, keratin
movement - create muscle contraction (fibrous) ex. actin and myosin
catalysts , transport, regulation of pH (globular)
regulation of metabolism, hormones, body defense (globular)
D. Nucleic Acids – contain carbon, hydrogen, nitrogen, oxygen, phosphate
Functions of nucleic acids: (DNA, RNA)
genetic code (DNA)
provides instructions for building proteins (DNA)
protein synthesis (RNA)
E. ATP – contains ribose sugar, 3 phosphate groups, adenine (basically an adenine nucleotide)
Functions of ATP:
useable energy to make and breakdown molecules
transport substances across membranes
muscle contractions
PHYSIOLOGY 103 Class 1 - Introduction
Summary
What are Anatomy and Physiology and How are They Related?
Anatomy vs. physiology
anatomy = structure and organization of body parts
physiology = functioning of body parts
Levels of Organization if the Human Body
Chemical Level
 atoms…..oxygen, carbon, hydrogen etc
 molecules……water, bicarbonate, carbon dioxide, protein
 organelles……mitochondria, ribosomes
Cellular Level
 cells…the smallest units of living things, all body parts are made of cells
 cells combine to form tissues
Tissue Level
 tissues are groups of similar cells with a common function
 4 basic types of tissues – epithelium, muscle, connective, nervous
Organ Level
 organ = structure composed of at least 2 tissue types that perform a specific function
Organ System
 organ systems are made up of organs that work together to accomplish a common
purpose
Organism Level
 highest level of organization = organism = human being
Necessary Functions for Life
1. Maintain boundaries
 ensures internal environment remains distinct from external environment
 encloses contents while restricting entry of damaging or unnecessary substances
2. Movement
 within our environment , within our body, within our cells
3. Responsiveness/Irritability
 ability to sense changes in the environment and respond to them
 nerve cells communicate rapidly and are highly irritable…sensitive to change and able
to send an electrical message in response
4. Digestion
 breakdown of ingested food to simple molecules to be absorbed into blood
5. Metabolism
 all chemical reactions that occur in the body
6. Excretion
 removing waste from the body
7. Reproduction
 cellular level – original cell divides producing 2 identical cells – used for growth and
repair
 organism level – reproductive system
8. Growth
 increase in size of a body part or the organism
 accomplished by increasing the number of cells or size of cells
Survival Needs
1. Nutrients
 chemical substances used for energy and cell building
 carbohydrates, proteins, fats, minerals and vitamins
2. Oxygen
 needed for the chemical reactions that release energy from food
3. Water
 environment for chemical reactions, fluid base for secretions and excretions
4. Normal Body Temperature
 must be maintained for chemical reactions to continue normally
5. Atmospheric Pressure
 breathing and gas exchange in the lungs depends on appropriate atmospheric
pressure
Homeostasis
 homeostasis = the body’s ability to maintain its relatively stable internal conditions
even though the outside world changes constantly
Regulating Homeostasis
 nervous system and endocrine system are the major systems involved….electrical
impulses and hormones allow communication
 receptor = a sensor that monitors the environment
 stimuli = change in the environment
 input = information from stimuli
 afferent pathway = carries information towards control centre
 control centre = integrative centre
 output = information being carried away from control centre
 efferent pathway = carries information away from control centre
 effector = performs the appropriate response
Negative Feedback
 if the body starts to deviate from optimal….response occurs to reduce the
deviation….return to original state
 causes a response opposite to what was occurring…..negative feedback
Positive Feedback
 response enhances the original stimulus so the activity is accelerated
 positive….means the response occurs in the same direction as the original
change/deviation/disturbance causing further deviation from the original state
Homeostasis and Stress
 stress stimulates the hypothalamus
 hypothalamus is the major homeostatic control centre of the body
 stimulates many glands to release hormones to attempt to return to homeostasis
 Cortisol is one hormone that is released…acts on many tissues, stress adaptation
hormone, steroid hormone
 mobilizes energy reserves
 enhances effects of epinephrine (Adrenaline) on vasoconstriction
 cortisol will suppress inflammation
 excess may cause decreased immunity, ulcers, depression of bone/cartilage formation
Physiology 103 Class 2 – Basic Chemistry
Summary
Atom
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smallest stable unit of matter (matter is “stuff”)
consists of subatomic particles…protons, neutrons, electrons
protons have a +ve charge, located in nucleus
neutrons are neutral, located in nucleus
electrons have a –ve charge, orbit the nucleus
all atoms are electrically neutral…# protons is balanced by # electrons
atoms of different elements are composed of diff numbers of those which makes them unique
and different from each other
Atomic Number
 atomic number = # of protons (indirectly tells us the #of electrons)…#electrons determines
chemical behavior
 different atoms have a different atomic number
The Elements
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elements are made of atoms with the same number of protons
ex. oxygen, carbon, gold, silver, copper, iron
112 elements
carbon, oxygen, hydrogen, nitrogen make up 96% of body weight
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most atoms combine with other atoms…form a chemical bond to form a molecule
ex. 2 hydrogen atoms = a hydrogen molecule H2
2 or more different kinds of atoms combine = a molecule of a compound
ex. H2O, CH4 methane
Chemical Bonds
 when atoms combine, they form chemical bonds….they are not a physical structure but an
energy relationship between the electrons of the reacting atoms
 electrons around the nucleus occupy regions called electron shells
 atoms can have up to 7 shells, number of shells depends on number of electrons
 electrons far from the nucleus have less attraction to their nucleus
 the farthest are most likely to interact with other atoms…they are the least tightly held by their
own nucleus
 each electron shell can hold a specific number of electrons
shell 1 – 2 electrons
shell 2 – 8
shell 3 – 18
 each shell fills before the next
 outermost shell interacts in bonding with other atoms
 inner electrons are held tighter…attracted to their nucleus
 if outer layer is full…..atom is stable….inert…unreactive…noble gases…..helium, neon
 atoms with fewer than 8 electrons in their outer shell will gain, lose or share electrons with
other atoms to become more stable…not stable with less than 8
ex. oxygen… has 6 electrons in outer shell….incomplete
ex. hydrogen…has one electron in its shell…..incomplete
ex. sodium…has 11 electrons……2, 8, and then 1 in outer shell…incomplete
atoms will combine with other atoms so that they end up having 8 electrons in the outer shell
Ionic Bonds
 electrons from atoms can be transferred from one atom to another……..they want to be
both structurally stable and electrically stable…….in natural state they are electrically
stable but they are structurally unstable …..with vacancies in their outer shell
 when an atom loses or gains an electron, its balance of + and –ve is lost and it is
electrically unstable and is called an ion
 If an atom gains an electron…..it has gained one more –ve bit….so it is called an ANION
and it is now negatively charged
ex. chloride…7 electrons in outer shell...wants to fill its outer shell…so it will find an atom with one
electron in its outer shell and steal that one…..when it accepts that one it now is stable
structurally but is electrically negative with one extra electron
 The atom that gave up the electron, gave up one bit of negativity so it is now
positive…CATION (positive relative to its resting state)
ex. sodium…one electron in its outer shell……will give up that one (and now the outermost
shell/valence shell has 8 in it and it is stable) to chloride so sodium standing alone would be na+
and the chloride alone would be cl because opposite charges attract….. the +ve sodium and the –ve chloride tend to stay
close together and form an IONIC bond
Covalent Bonds
 Some bonds may be formed by sharing their outer ring so they can fill their outer rings
and be stable…they don’t transfer the electrons
 that shared orbital becomes a single orbital common to both atoms…COVALENT
BOND…strong bonds
 common examples…H2 O2 CO2 H2O CH4
Single vs. Double covalent bonds
in the above examples:
H2…each H needed to share one electron….single bond
O2…each O2 needed to share 2 electrons …. double bond
(much more efficient that sharing one with 2 separate ones)
CH4…C needed 4 and each H needed one so 4 single bonds
CO2…C needed 4 and each O needed 2 so 2 double bonds
H2O…O needed 2 and each H needed one so…single bond
Phys 103 Class 3 - Biochemistry
Summary
Biochemistry
 the chemicals and reactions of living matter
 organic = contain carbon, are covalently bonded, protein, carbs, fats
 inorganic = all other chemicals in the body…water, salts, acids, bases
Inorganic compounds
A. Water
B. Salts
C. Acids and Bases
A. Water
Functions of water
1. Formation of Solutions
 water is the solvent for many chemicals (solutes) to react
 nutrients, respiratory gases and metabolic wastes dissolve in blood to be transported
through the body
2. Reactivity
 water is a reactant in many chemical reactions
 ex. foods during digestion break down into their building blocks by adding water
molecule to each bond to be broken -- hydrolysis
 ex. large CHO or PRO molecules are synthesized from smaller molecules, water is
removed from every bond formed – dehydration
 hydrolysis - water molecule causes other molecules to split. ex. long CHO
molecule….the water molecule splits and the OH joins the part released from the chain
and the H fills the space that was vacated on the end of the chain
 dehydration synthesis - 2 molecules join and H2O is released ex. making glucose in
the body….gluconeogenesis….as another molecule is added to the chain, an H comes
off the existing chain and an OH comes off the part to be added on and that piece is
added and the H2O is made and released
3. Temperature Regulation
 water absorbs and releases large amounts of heat before changing temperature
noticeably
 prevents sudden changes in body temp caused by external factors or changing
internal factors
 redistributes heat among body tissues via blood to maintain temperature homeostasis
 when large amounts of heat are absorbed the hydrogen bonds are broken that hold
H2O together, allowing evaporation…sweat to occur
 as water evaporates from our skin large amounts of heat are removed from the body
providing a cooling mechanism
4. Cushioning
 forms a resilient cushion around certain body organs…protecting them from physical
trauma ex. CSF around brain
5. Lubrication
 lubricating molecules such as mucus are water based
B. Salts
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salt = ionic compounds containing cations other that H+ and anions other than the OHex. NaCl, KCl, CaCO3
when dissolved in water the dissociate into their component ions
this occurs easily because the ions are already formed, the water just needs to
overcome the attraction between the ions
 carry an electric current in water…..electrolytes…when forming their ionic bond, they
became charged, when they split in water that neg or pos ion exerts a pull on other pos
or neg ions which creates movement of ions, creating an electric current
 nerve impulse transmission and muscle contraction depend on the electrolyte
properties
C. Acids and Bases
Acids - substance that releases H+ when they dissolve in water (proton donor)
Bases - substance that releases OH- in water, and take up H+ ions in water (proton acceptors)
pH - Acid Base Concentration
 more hydrogen = more acidic = lower pH
 more OH = more basic/alkaline (means there is less H+) = higher pH
 scale from 0-14
 each increase in 1 number is a 10 fold increase in concentration
 at pH 7 amount of H = amount of OH
 as H increases there is relatively less OH
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ex. red food colouring = acid, blue food colouring = base
neutral = purple
add red….more acidic….more H now…more H than OH
add blue…more basic….more OH now…..more OH than H
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as you increase the amount of hydrogen in solution…..the ph goes from 7 to 6, 5, 4, …
as you increase the amount of OH in solution ….ph goes from 7 to 8, 9,10...
going from 7 to 6 means you added 10 times the existing amount of H in solution
going from 7 to 8 means you removed 10 times the existing amount of H in solution,
but how do you remove H? add OH to bind to it, so going from 7 to 8 you increased the
amount of OH by 10 times
 again….the blue and red…….at 7 it is purple
 at 4 you added more red…more H….more acidic…..now more red than blue, more H
than OH…
 at 8 you added more blue…more OH…more basic… or took away some red so you
have less red now…less H than OH….. and more blue….more OH
 H and OH are opposites...if you think from neutral….as you increase the H, the relative
amount of OH in relation to the whole solution is now decreasing, if you do not add or
subtract any OH the number of particles is staying the same but it is now taking up a
smaller amount of that total solution
 pH above 7 is called a base or alkaline, pH below 7 is acidic
 as H increases, the relative amount of OH decreases, and as H decreases, the relative
amount of OH increases
 as OH increases, the relative amount of H decreases, and as OH decreases, the
relative amount of H increases
Buffers
 lungs and kidneys work to regulate our ph by a chemical system of BUFFERS
 if pH of a solution gets too high…to basic…a buffer will release some of its H into the
solution
 if pH of a solution gets too low….too acidic….a buffer will pick up some of that H and
binds it to itself and carry it away so there is less H is that solution now
 weak acids and weak bases have the ability to lose or gain H and OH
 weak acid H2CO3 - carbonic acid
 weak base HCO3 - bicarbonate
 when pH rises (basic) due to low H in solution or high OH in solution…..the weak
acid….H2CO3 will release H …that addition of H will decrease the pH, increase the
acidity (when the H2CO3 lost the H it became HCO3, a weak safe base, and the H
floats free or binds to OH to make H2O….bringing the pH from basic down towards
neutral)
 when pH falls (acidic) due to high H in solution or low OH in solution…..the weak
base…HCO3 will bind the H ….. that removed the H from solution and will increase
the pH, decrease the acidity (when the HCO3 picked up the H it became H2CO3, a
safe acid)
 H2CO3 weak acid ….releases H if not enuf H in blood (high pH, basic)…released H
will add H to blood….decreases the pH, increase the acidity…….H2CO3 now becomes
HCO3…weak base…ok in blood
 HCO3 weak base…binds H if there is too much in blood (low pH, acidic)……removing
free H from blood……increases the pH, decreases the acidity….more basic……HCO3
now becomes H2CO3…weak acid….ok in blood
ORGANIC COMPOUNDS
Carbohydrates
 sugars and starches
 carbon, hydrogen and oxygen
 hydrogen and oxygen usually appear in a 2:1 ratio
Monosaccharides
 one sugar, simple sugar, chain or ring of 3-7 carbons
 1:2:1 ratio of carbon:hydrogen:oxygen
 ex, glucose C6H12O6
Disaccharides
 double sugar, 2 monosaccharides are joined
 sucrose-----glucose and fructose table sugar
 lactose------glucose and galactose milk
 maltose------glucose and glucose malt sugar
 must be digested to their smaller units to be absorbed into blood
 this is hydrolysis…adding water allows the bonds to break between each unit
Polysaccharides
 long chains of simple sugars linked together
 insoluble, ideal storage molecules, ex. starch and glycogen
Physiology 103 Class 4 - Lipids
Summary
Lipids
 insoluble in water
 dissolve in other lipids
 contain carbon, hydrogen and oxygen
 low amounts of oxygen
 some have phosphorous
Types of lipids:
 triglycerides
 phospholipids
 steroids
1. Triglycerides (Neutral Fats)
 solid = fat
 liquid = oil
 come from food and we produce them from eating excess calories
 made of 1 glycerol and 3 fatty acids
 fatty acids – carbon and hydrogen chains with a COOH group on the end
 glycerol – modified simple sugar – 3 carbon molecule
 triglyceride is 3 fatty acids joined to a glycerol backbone
 they do not mix with water
 they are the most efficient and compact form of stored energy
Functions of Triglycerides:
 found beneath the skin
 insulate deeper tissues from heat loss
 protect deep tissues from mechanical trauma
Saturated and Unsaturated
 length of fatty acid and degree of H saturation determines how solid it is
 saturated = all single covalent bonds between carbon
 these are straight, packed closely together, form a solid at room temp
 unsaturated = one or more double bonds between carbons
 one double bond = monounsaturated
 more double bonds = polyunsaturated
 double bonds cause the chain to kink so they cant be packed close enough to be solid
 trans fats
 oils that have been solidified by adding H at double bond sites
 unhealthy
 omega 3 fatty acids
 healthy
 polyunsaturated fatty acids
2. Phospholipids
 modified triglycerides
 glycerol and 2 fatty acid chains (nonpolar tail)
 phosphorous group (polar head) – attracts other polar/charged molecules…water,ions
 this polar/nonpolar characteristic is important in building cell membranes
Steroids
 4 interlocking hydrocarbon rings
 fat soluble
 contain little oxygen
Cholesterol
 eat in animal products…eggs, meat, cheese
 we produce some in our liver
 found in cell membranes, in vitamin D, hormones, bile salts
Physiology 103 Class 5 – protein and nucleic acids
Summary
Proteins
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10-30% of cell mass
basic structural material of the body
enzymes, hemoglobin, contractile proteins
contain carbon, oxygen, hydrogen and nitrogen
Amino Acids
 building blocks of proteins
 20
 have amine group and organic acid group NH2 and COOH
 amino acid is made of: an H atom, amino group,carboxylic acid group, variable group
 amino acids join to form peptides
 2 makes a dipeptide, 3 makes a tripeptide
 10 + makes a polypeptide, 50+ makes a protein
 usually proteins have 100 to 10000 +
Structure of Proteins
primary structure
polypeptide chain of amino acids
secondary structure
alpha helix – coils
beta pleated sheet - accordian
tertiary structure - ball
quaternary structure - complex protein
Classified as Fibrous or Globular
Fibrous – strandlike
 many have secondary structure, some are quaternary
 insoluble in water, very stable
 mechanical support, tensile strength
 aka structural proteins…..chief building materials of body
 Functions:
support:
collagen – in connective tissue, bones, tendons, ligaments
keratin – structural protein of hair and nails
elastin – for durability and flexibility - ligaments
movement:
actin and myosin – in muscles – create muscle contraction
cell division
intracellular transport
Globular
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compact, spherical, at least tertiary structure
water soluble, chemically active, role in all biological processes
aka functional proteins
Functions:
catalysts – salivary amylase…starch breakdown
transport – hemoglobin – oxygen, lipoproteins transport lipids
regulation of pH – some plasma proteins act as buffers
regulation of metabolism – hormones…growth hormone, insulin
body defense – antibodies
Nucleic Acids
 composed of C, H, N. O, P
 largest molecules in the body
 store and process information inside cells
Structure of Nucleic Acids
 long chain of nucleotides - nitrogen, sugar (C, H, O) and phosphate
 DNA is made of the sugar deoxyribose (same as ribose but with an extra OH)
 RNA is made of the sugar ribose
 the nitrogen containing groups are called adenine, guanine, cytosine and thymine in
DNA but uracil in RNA
 nucleotides join together …the sugar from one attaches to the phosphate of the next
then that sugar joins the next phosphate and so on and the nitrogen group hangs off
the sugar
 DNA is 2 chains of nucleotides that line up together and the nitrogen groups/bases
across from each other forms a bond …..so that a ladder-like molecule is created
 the sugar and phosphate for the backbone and the bases form the rungs
 the whole molecule coils like a spiral staircase…now called a double helix
 when the bases pair up, A bonds with T and G bonds with C
 RNA is a single strand
Role of DNA:
 genetic code
 DNA replicates itself before a cell divides, so that new cells have the same genetic
blueprint in them
 DNA provides instructions for building every protein in the body…protein is the basic
structural material of the body
 DNA has the instructions for protein production….directs growth and development,
instructs RNA what proteins to make
Role of RNA:
 takes orders from DNA and makes the appropriate protein
ATP
 adenine nucleotide…ribose sugar, 3 phosphate groups (triphosphate) and adenine
joined to it
 ATP is created by capturing energy released from breaking down glucose and storing
it in the bonds between the phosphate groups
 ATP is then useable as a form of energy by body cells
 the bonds between the phosphate molecules are broken using enzymes which transfer
the phosphate groups from ATP to other compounds, which “phosphorylates”
molecules and “primes” them so they are ready to work
 when that P is taken off….ADP is left
 ATP is replenished when glucose is broken down and phosphates are transferred from
various molecules in the process and ATP is recreated
 ATP used to make and breakdown molecules, transport substances across
membranes, muscle contractions, etc.
Class 6 – The Cell - Summary
Cell Types
 shape reflects function
 cells generally have the same basic parts and some common functions
Parts of a Cell
1. Plasma Membrane
2. Cytoplasm
A. Cytosol
B. Organelles – Membranous: a. endoplasmic reticulum, b. golgi apparatus, c. lysosomes
d. peroxisomes, e. mitochondria
Nonmembranous: a. cytoskeleton, b. ribosomes, c. centrosomes
d. centrioles
3. Nucleus - Nuclear Membrane, Nucleolus
1. Plasma Membrane
 separates intracellular fluid and extracellular fluid outside the cell
 regulates movement of substances in and out of cell
 fluid mosaic model - bilayer of phospholipid molecules with protein, cholesterol and
glycolipid molecules dispersed in it
 proteins:
integral: transport channels for water soluble molecules or ions, carriers for
various substances, receptors for hormones
peripheral: support the membrane, some are enzymes, some
help in cell
division, some form the glycocalyx
2. Cytoplasm
 cytosol plus organelles
A. cytosol – fluid in which the other things are suspended
B. organelles - membranous
a. Endoplasmic Reticulum
 extensive system of interconnected tubes and parallel membranes enclosing fluid filled
cavities that coils and twists through the cytosol
 RER – ribosomes on outside – secretory proteins, integral proteins and phospholipids
are made here and enter the ER
 SER – tubules with enzymes that catalyze reactions involved in:lipid metabolism,
cholesterol synthesis, lipoprotein synthesis, steroid hormone synthesis, synthesis of fat
detoxification of drugs, pesticides, carcinogens, breakdown of stored glycogen to form
glucose
b. Golgi Apparatus
 “traffic director” for cellular proteins - modifies, concentrates and packages proteins
and lipids made at the RER
 transport vesicles bud off from RER, fuse with golgi
 proteins are modified – sugar groups trimmed or added, phosphate added
 the proteins are tagged for delivery to a specific address, sorted and packaged in
vesicles that bud from the other side of the golgi….vesicles pinch off and and go to
plasma membrane and release their contents via exocytosis and pinches off vesicles
with lipids and membrane proteins bound for plasma membrane
c. Lysosomes
 contain digestive enzymes, digest invading bacteria viruses and cell debris, degrade
worn-out organelles
 metabolic functions - glycogen breakdown for release
d. Peroxisomes
 powerful enzymes - oxidases - detoxify harmful substances – alcohol, formaldehyde,
neutralize free radicals…highly reactive chemicals with unpaired electrons that can
scramble the structure of biological molecules
e. Mitochondria
 produce ATP, power plant of the cell
 intermediate products of food fuels…glucose…are broken down to water and CO2
here in various parts of the mitoch membranes
 energy is captured as metabolites are broken down and ATP is formed with high
energy bonds
B. organelles : Non Membranous
a. Cytoskeleton
 cell skeleton
 microtubules, microfilaments, intermediate filaments
o microtubules
- determine cell shape and organelle distribution
o microfilaments - cell motility or change cell shape
o intermediate filaments - internal guy wires to resist pulling forces
b. Ribosomes
 site of protein synthesis
 some are free, some are attached to RER
free – make soluble proteins that function in the cytosol
on RER – make proteins for cell membrane or for export from cell
c. Centrosome
 microtubule organization centre, near nucleus
d. Centrioles
 form microtubules needed for mitosis
 form the basis of cilia and flagella
Cilia and Flagella
Cilia - motile cellular extensions, moves substances across cell surface
Flagella - longer projection that propels the cell
3. Nucleus
 control centre
 contains instructions for building body’s proteins
Nuclear envelope
 double membrane barrier with fluid filled space
 has pores that allow stuff in and out
 contains nucleoplasm
Nucleoli
 found in nucleus, site of assembly of ribosome subunits….large in growing cells and
cells that make lots of protein
 contains chromatin/chromosomes…DNA
plasma membrane – fragile membrane, outer boundary of cell
protoplasm - all the fluid in a cell…cytoplasm and nucleoplasm
cytoplasm – intracellular fluid that is packed with organelles
cytosol - fluid in which the other things are suspended
endoplasmic reticulum – protein synthesis (RER), lipid synthesis and metabolism (SER)
golgi apparatus – modifies and packages proteins
lysosomes – digestion of bacteria, viruses, worn out organelles etc.
peroxisomes – detoxifies harmful substances
mitochondria – ATP synthesis
cytoskeleton – cell support, shape and movement
ribosomes – protein synthesis
centrosome – microtubule organization
centrioles – form microtubule network for cell division
nucleus – controls cells activities, transmits genetic information and instructions for protein
synthesis
Physiology 103 Class 7 Summary
Fluids
Intracellular Fluid
 2/3 of body’s water…inside cells
Extracellular Fluid
 1/3 of body water …outside/surrounding the cells
 ECF is….blood plasma (btw blood cells) and interstitial fluid (btw other cells)
 carries nutrients, ions, wastes, maintains homeostasis
Composition of Fluids
ICF :high K, Mg, PO4, low Na, Cl, HCO3, some protein
ECF:high Na, Cl, HCO3, low K, Mg, PO4, also O2, glucose, fatty acids, amino acids, CO2, waste
Plasma Membrane
Functions
1. control cellular contents
 membrane controls entry and exit of nutrients, ions etc…..to maintain homeostasis in
cell
2. communication
 receptors on cell…ex. neurotransmitter receptors on muscle/nerve cells allow
communication among cells
3. structural support
 structural proteins in cell give it shape, allow cells to connect physically
Structure of the Plasma Membrane
 fluid bilayer of phospholipids, selectively permeable
 embedded proteins, CHO, cholesterol
integral proteins: transmembrane - span the width
 functions: anchors structures to cytoskeleton, receptors, carriers, transport
channels or pores
peripheral proteins:attached to integral proteins or to lipids in membrane
 functions: support the membrane, enzymes, help in cell division, some form
the glycocalyx…sugar coating/fingerprint of the cell
carbohydrates: on outer surface, form the glycocalyx
Permeability of substances through plasma membrane
…allows nutrients in, keeps undesirable stuff out
…keeps valuable proteins in, allows wastes out
1. Fat soluble substances:
 vitamin A, fatty acids, steroids…..pass easily though due to lipids in membrane
2. small uncharged molecules
 O2, CO2, H2O, urea…pass easily…..may slip between the tails
3. small charged particles and larger particles
 ions and larger molecules…proteins….do not pass
 pass only through special protein channels
Transport Through Plasma Membrane
1. Active Processes – require energy
2. Passive Processes – no energy required
2 Main Passive Processes: Diffusion and Filtration
Diffusion
 tendency of molecules to distribute evenly in an environment
 molecules move away from areas where there is higher concentration and move
towards areas where there is lower concentrations
 ….molecules move along/down their concentration gradient
 diffusion will occur until there is no net movement……equilibrium has been reached
between the 2 areas
Rate of Diffusion
1. size of gradient - greater difference between the 2 areas = faster movement
2. size of molecule - smaller = faster movement
3. electrical charge - like charges repel, opposites attract
4. temperature - warmer = faster diffusion
Types of Diffusion
1. Simple Diffusion
 non polar and fat soluble substances diffuse through lipid bilayer
 oxygen, CO2, fat soluble vitamins….ADEK
 O2 – concentration higher in blood than cells….so always diffusing into cells
 CO2 – concentration higher in cells…..so diffuses into blood
2. Facilitated Diffusion
 some molecules….glucose, other sugars, amino acids, ions
 bind to protein carrier in membrane and are taken across membrane or
 moves through a water-filled protein channels
3. Osmosis
 diffusion of water through a selectively permeable membrane
 osmosis occurs when water concentration differs on 2 sides of a membrane
 water will move from an area where there is low solute concentration to high solute
concentration….to evenly dilute a solution
 example…..a container with a membrane that is permeable to water and
sugar…….water will move for the area of lower concentration of sugar to higher
concentration of sugar…..if sugar is allowed to move, it will move to reach equilibrium
 ex. impermeable to sugar…if that membrane is impermeable to sugar…water will
move into the compartment with more sugar
 the particles pulled water towards them,………osmotic pull….osmotic pressure
 osmotic means concentration
 osmolarity means how many solute particles are in a solution…..so the more solutes =
greater osmolarity = greater tendency to pull water towards it
Tonicity
 ability of a solution to change the shape of a cell by altering internal water
volume…this is done by solutes pulling or pushing water towards or away from them
isotonic solution - solution with same concentration of the cell...no water movement
hypertonic solution - solution has a higher concentration of solutes than the cell does…this
pulls water out the cell into the solution…cell shrinks
hypotonic solution - solution has lower concentration of solutes/more dilute/more water than the
cell…water rushes into the cell…cell bursts
Filtration
 water and solutes forced through a membrane by pressure
Class 8 Summary
Active Transport, Membrane Potential
Active Processes
• requires energy…ATP…to move substances across a membrane
• substances are unable to pass through the membrane passively…substances are too large, or
incapable of dissolving in the lipid layer, or unable to move down their concentration gradient
2 types of active transport:
active transport – movement against chemical gradients
primary
secondary
vesicular transport – movement of large particles into or out of cell
Active Transport
• carrier proteins combine specifically and reversibly with a substance
• movement is against concentration gradient
• powered by ATP
• typically moves ions Na, K, Ca
1a. primary active transport
• ATP is used directly to move substances against a gradient
• ex. Na/K pump…an exchange pump
• hydrolysis of ATP causes the phosphate to attach to the protein carrier…causes the protein to
change its shape so that it pumps the bound substance across the membrane
• ex. Na/K pump …Carrier is a protein/enzyme called Na/K ATPase
• Na is high in ECF, K is high in ICF
• Na and K constantly leak thorough leakage channels…Na leaks in, K leaks out…. but it is
important to return them to their proper places
• Na/K pump works continuously to take Na back out of cell and K into cell
1b. secondary active transport
• Na leaks into cell down its concentration gradient with use of a carrier protein (facilitated
diffusion)…..this pulls/drags/cotransports glucose with it
• Na and glucose movement is passive but Na has to be pumped back out into the ECF to
maintain its diffusion gradient
• Na/K pump uses energy/ATP to pump Na back out…to return Na to its proper place in ECF and
to re-establish that concentration gradient…that high Na in ECF is important as it is that Na
gradient that makes Na leak into the cell and pull glucose with it
Vesicular Transport
• Moving large molecules into or out of cells
Endocytosis
• moving substances from ECF into cell
• substance is enclosed by an infolding portion of the plasma membrane, membrane pinches off
and the vesicle enters the cell
• lysosome degrades it and the contents is degraded or released
Phagocytosis
- cell eating
- solid material engulfed by cell….bacteria, cell debris, nutrients
- particle binds to receptors on cell surface, forms a vesicle called a phagosome, once inside the
cell, fuses with a lysosome and the contents are digested
Pinocytosis
- cell drinking
- fluid with dissolved molecules is surrounded by infolding of cell membrane
- enters cell, vesicle is degraded and fluid and dissolved particles enter cell
- this happens regularly as a means to sample the ECF, especially important for intestinal cells
that absorb nutrients
Receptor mediated endocytosis
- endocytosis of specific substances….hormones, cholesterol, iron
- particular substances bind to specific membrane protein receptors
Exocytosis
• moving substances from the interior of the cell into the ECF
• ex. Hormone secretion, ejection of wastes, etc…
• substances is enclosed in a vesicle, moves to plasma membrane, fuses with membrane,
ruptures…contents spill into ECF
Resting Membrane Potential
plasma membrane is selectively permeable…
• This causes some things to accumulate on each side of the membrane as they are not allowed
to pass through it….some of those things …Na, K….have charges
• This creates Membrane Potential/Voltage/difference in charge across the membrane
• Inside of membrane is negative relative to outside (-70mV)
Resting State – K+ high concentration inside cell, Na high concentration in ECF
Outside…..lots of Na+ along membrane
Inside…..lots of K + along membrane but not as much K+ along membrane as there is Na
outside ...therefore…less + inside…so inner side of membrane is relatively negative
This exists only at the membrane….the majority of the cell is neutral as is the ECF
The Na and K gather at the membrane because they want to cross the membrane because of
their concentration gradient
How is the membrane potential established?
Mainly by concentration gradient of K+ and the difference in membrane permeability to K and Na
Resting state…..
Membrane is a little permeable to K…leakage channels……K diffuse out a little down its
gradient….inside is losing some +ve so it is becoming negative (from -70 to -90)
Membrane is only a tiny bit permeable to Na so some Na will enter down its concentration
gradient, this ….takes membrane back up to -70
Active transport processes maintain the membrane potential…Na/K pump works to maintain the
membrane potential…..
Pumps 3 Na+ out and 2 K+ in………so that K that leaked out and that Na that leaked in is
stopped and they are sent back to their proper places so that strong gradient is maintained
In pumping 3 Na+ out and 2 K+ in…..the inside is not becoming as +ve as the outside, less + is
being pumped in, so the inside is staying relatively –ve and K+ is returning inside and Na+
outside
Phys 103 Class 9 – Cell Reproduction
Summary
Cell Reproduction
Cell life cycle = series of changes a cell goes through from formation until
reproduction…….consists of: interphase and cell division
Interphase = cell growth and normal activities
Cell division/mitosis = cell divides into 2 cells
Interphase
from cell formation to cell division
cell is carrying on its normal activities, in between cell divisions
G1 - growing rapidly, making proteins, at end of G1, centrioles replicate to prepare for cell division
S - DNA replication, cell still growing and carrying on normal activity too
G2 - enzymes and proteins needed for division are made, cell still growing
DNA Replication
Identical copies of genetic code must be passed on to offspring before a cell can divide
1. DNA double helix unwinds
2. Enzyme separates it into 2 strands of nucleotide chains, exposing the nucleotide bases
3. Each strand is a template for a new complementary strand of nucleotides created from free
floating DNA precursors floating in the nucleoplasm
4. Enzymes and DNA precursors accumulate at replication site
5. DNA polymerase (enzyme) positions complementary nucleotides along the template and links
them together, creating a long chain
6. Replicated segments are joined together resulting in 2 DNA molecules formed...each DNA
molecule has an old and new strand
7. Replication is over, DNA condenses to form chromatids, chromatids are attached by a
centromere
Cell Division
Mitosis - events that delivers the replicated DNA to 2 daughter cells
4 phases – prophase, metaphase, anaphase, teophase
Cytokinesis - plasma membrane is drawn inward until the cytoplasmic mass is pinched
into 2 daughter cells
each daughter is smaller and has less cytoplasm but is genetically identical to the mother
they then enter interphase until it is their turn to divide
Interphase
DNA is condensed chromatin
microtubules extend from centromeres
centrioles replicate from one pair to 2 pairs
DNA replicates
Early Prophase
microtubule asters extend around centrioles
chromatin coils and condenses to form chromosomes - 2 identical chromatin threads (chromatids)
chromatids of a chromosome are held together by a centromere
centriole pairs separate from each other
centrioles grow microtubules…..mitotic spindle….this pushes the centrioles farther
Late Prophase
centrioles still moving apart
nuclear envelope disappears
mitotic spindle microtubules attach to chromosome centromeres
chromosomes are being pulled towards centre of cell
Metaphase
chromosomes line up along middle of cell
Anaphase
centromeres of each chromosome split and one chromatid is pulled towards one end of the cell
and the other is pulled the other way
each chromatid is now called a chromosome
the microtubles push the poles of the cell apart, causing the cell to elongate
Telophase
identical sets of chromosomes are now at opposite ends of the cell
chromosomes uncoil into threadlike chromatin
new nuclear envelope develops from floating fragments of the original envelope
spindle disappears
Cytokinesis
completes the division into 2 cells
contractile ring of microfilaments forms at the midline and squeezes the cells apart towards
opposite ends of the cell
Phys 103 Class 10 – Protein Synthesis
Protein Synthesis
DNA’s 2 roles:
 replicate itself prior to cell division
 provides instructions for protein synthesis
gene: a segment of DNA that carries instructions for creating one polypeptide chain…the
sequence of ATCG nucleotides is the code of specific proteins to be made
triplet: a sequence of 3 bases …a specific code for a specific amino acid
ex.
TTT is the DNA code for phenylalanine
GGG is the DNA code for glycine
the sequence of triplets in each gene is like a sentence……code for a polypeptide…specifies
the type, number and order of amino acids needed to build that polypeptide chain
so basically….
sequence of DNA triplets is transcribed to a sequence of mRNA codons and that is translated to a
string of amino acids which form a protein
 one strand of DNA has a code for a particular protein (coding strand/sense strand)
 its complementary strand serves as a template
 template strand is copied to produce a strand identical to the coding strand (with the
exception of the A and U thing)
 so the template is actually copied to create the mRNA
ex. phenylalanine
DNA triplet = TTT (AAA is template)
RNA codon = UUU
ex. proline
DNA triplet = CCT (GGA is template)
RNA codon = CCU
Role of RNA
 DNA information can only be used if it s decoded……needs a “decoder”
 DNA stays in the nucleus and most protein is made on ribosomes in the
nucleus….needs a “messenger”
 RNA does the decoding and messenging
 RNA……similar to DNA but is single strand and has uracil instead of thymine
 3 types of RNA work together to carry out DNA’s instruction
transfer RNA…..tRNA…small molecule that brings amino acids to ribosome
ribosomal RNA….rRNA…constructs the ribosome
messenger RNA…mRNA…carries the info from sense strand of DNA to ribo
2 stages involved in polypeptide synthesis…
transcription…DNA’s information is encoded in mRNA
translation…information carried in RNA is decoded and used to assemble polypeptides
Transcription
 transfer of information from a DNA gene’s base sequence to the complementary base
sequence of an mRNA molecule
 mRNA detaches from DNA, leaves the nucleus
 RNA polymerase unwinds 16-18 base pairs of DNA…then incoming ribonucleotides
are aligned with complementary DNA bases on the template strand and joins the RNA
nucleotides together
ex. DNA template triplet AGC…..the mRNA sequence synthesized at that site will be UCG (the
coding triplet would have been TCG)
Translation
 language of nucleic acid (base sequence) is translated into the language of proteins
(amino acid sequence)
 occurs in cytoplasm
 involves mRNA, tRNA and rRNA
 in cytoplasm, mRNA binds to small ribosomal subunit by pairing to rRNA
 tRNA comes and transfers amino acids to the ribosome, maneuvers the amino acid
into the proper position as specified by the mRNA codon
 tRNA has amino acid bound to one end , anticodon at other end….3 base sequence
complementary to the mRNA codon calling for the amino acid carried for that tRNA
ex. mRNA codon UUU phenylalanine….tRNA carrying phenylalanine will have anticodon AAA
 ribosome holds the tRNA and mRNA close together to coordinate the coupling of
codons and anticodons and positions the next amino acid for addition to the growing
chain
initiation of translation……
 mRNA attaches to small ribosomal subunit
 large ribosomal subunit attaches to the smaller one…forms a functional ribosome with
mRNA positioned in the groove between the two subunits
 ribosome slides the mRNA along, bringing a codon into position to be read by a tRNA
 tRNAs continually transfer their amino acids onto the growing chain and then the
tRNAs move along and exit from the ribosome
 polypeptide is then released from the ribosome and the ribosome subunits separate
EPITHELIAL TISSUE
Simple Squamous
 for filtration or exchange of substances by diffusion
 kidney filtration membrane, alveoli walls in lungs, lines heart and blood vessels, lines
ventral body cavities and covers organs
Simple Cuboidal
 for secretion and absorption
 found in kidney tubules, ducts of glands, ovaries
Simple Columnar
 for absorption and secretion, has microvilli….for absorption, goblet cells …secrete
mucus
 in digestive tract, some have cilia…uterus and bronchi
Stratified Squamous
 protection
 forms outer layer of skin and extends a little into all body openings,
epidermis…keratinized
Stratified Cuboidal
 rare – sweat glands and mammary glands
Stratified Columnar
 rare – pharynx, urethra
Transitional
 cells stretch and permit distension
 bladder
Pseudostratified Columnar
 absorption and secretion, may have goblet cells…secretes mucus, may have cilia
 respiratory tract
CONNECTIVE TISSUE
Areolar Connective Tissue
 supports and bind other tissues, holds fluid, infection defense, stores nutrients
 widely distributed in body, wraps blood vessels, glands, nerves, forms subcutaneous
tissue that cushions skin and attaches skin to underlying structures
Adipose Tissue
 fuel reserve, insulation, protection
 accumulates in subcutaneous tissue, surrounds kidneys, behind eyes, accumulates at
genetically determined fat deposits such as abdomen and hips, located around organs
Reticular Connective Tissue
 forms a framework that supports blood cells in lymph nodes, spleen, bone marrow
 nodes, spleen, bone marrow
Dense Regular
 provides strength and resistance to tension where tension is exerted in a single
direction
 tendons and aponeuroses, fascia, ligaments
Dense Irregular
 forms sheets in areas where tension is exerted from many directions
 skin…dermis, fibrous joint capsules, fibrous coverings of some organs…kidneys,
bones, cartilage, muscles, nerves
Hyaline Cartilage
 firm support, some pliability
 articular cartilage, tip of nose, connects ribs to sternum, supports respiratory passages,
embryonic skeleton, epiphyseal plates in children
Elastic Cartilage
 where strength and stretchability is needed
 external ear, epiglottis
Fibrocartilage
 where strong support and ability to withstand heavy pressure needed
 intervertebral discs, knee menisci
Bone
 supports and protects body structures, cavities for fat storage and synthesis of blood
cells
Blood
 carries nutrients, wastes, gases and other substances
MUSCLE TISSUE
 responsible for
 body movements
Skeletal - support the skeleton and allow movements of bones at joints
Cardiac - in walls of heart, contraction propels blood through blood vessels
Smooth - in walls of hollow organs, squeezes substances through the organs
NERVOUS TISSUE
 regulates and controls body functions
neurons – generate and conduct nerve impulses
supporting cells – nonconducting cells, support, insulate, protect neurons
Metabolism
metabolism = all the biochemical reactions that occur in the body
 catabolism - breaking down of complex substances……fat, CHO, proteins….into
simpler ones…fatty acids and glycerol, glucose, amino acids, they can be further
broken down in cells to acetyl coA and then used to make energy ….ATP…..
 anabolism - building of substances….cell components, organelles, cells, tissues,
enzymes, proteins, membranes
 cells extract energy from the breakdown of foods (catabolism) and use energy to build
(anabolism)
basically……
 energy is released (due to transferring of electrons) in the process of breaking down
nutrients (catabolism) to its it most basic components….C, H, O, N
 the energy is stored in ATP in high energy chemical bonds between the P molecules
 the cell then uses that ATP for building (anabolism) cell components, for muscle
contraction, for membrane transport
Energy Usage and ATP
 when nutrients are broken to their simple components (catabolism) electrons are
transferred from molecules and trapped in the bonds of ATP
 ATP is a high energy molecule……stores energy in the chemical bonds of P molecules
 ATP releases its energy to do work…..does this by phosphorylation…enzymes shift
high energy phosphate groups from ATP to other molecules which phosphorylates
them and causes them to increase in activity, produce motion or do work
 ATP with the help of an enzyme changes to ADP and gives the P and energy from that
bond to another molecule
Cellular Respiration
 the group of catabolic reactions where food fuels especially glucose are broken down
in cells and some of the energy released is captured to form ATP
 nutrients are broken down and are oxidized……O2 is added to them and they are
oxidized
 they lose electrons to the O2 molecule
 those electrons will be transferred in a series of reactions and the energy will be
captured as ATP
 specific enzymes allow this to occur
…purpose is to harvest electrons from the energy rich molecules of glucose…..and use those
electrons to be stored in the phosphate bonds of ATP
Redox Reactions
 oxidation – reduction reactions
 these types of reaction occur during the process of cellular respiration
oxidation = adding oxygen to another element…causes a change in the element
……..adding O2 causes 2 electrons to be removed and given to the O2
……..removing 2H causes 2 electrons to be removed
so the proper definition is……
oxidation is the gain of oxygen or loss of hydrogen
(both result in electrons being removed from the original molecule)
so…..the oxidized substance loses electrons ….or nearly loses the electrons…recall covalent
bonds……they don’t actually lose the electrons… they share them but oxygen is greedy and the
electrons that are being shared spend more time with the oxygen molecule.....with
hydrogen…when hydrogen is part of a molecule of other stuff, its lone electron is pulled to hang
out with the other atoms in the molecule, but when H splits from the molecule……it pulls its lone
electron with it.
 with food breakdown in cells….food is oxidized in a step by step process
 step by step removal of pairs of hydrogen molecules occurs…in removing H molecules it
pulls its electron with it…..so pairs of electrons are being removed in a step by step
process
 the eventual result is CO2 and H2O………………..from……glucose…..C6H12O6
 in the end the removed electrons will combine with O2 to form H2O
 so…..one substance is losing electrons…..it is oxidized …the food item
 those electrons do not just float free….another molecule must pick them up
 so……one substance gains electrons after one loses them
 the substance that gains the electrons is “reduced”……getting more negative
 so the reactions are called oxidation-reduction or redox
bottom line:
oxidized = loses energy
reduced = gains energy
since energy rich electrons are transferred from one substance to the next
so basically…..food is oxidized and the energy is transferred to a series of other molecules and
ultimately to ADP to make ATP
Enzymes
 enzymes are needed to make this happen…help with H+ removal
 the enzymes need help from coenzymes
Coenzymes
 the coenzymes can be hydrogen/electron acceptors…NAD+ and FAD (f
 NAD will accept those H and reduce to NADH2
 FAD will accept those H and reduce to FADH2
Processes Involved in Cellular Respiration
1. Glycolysis
 breaking down/oxidizing glucose to make:
pyruvic acid or lactic acid
a very small amount of ATP
2. Formation of Acetyl coA
 pyruvic acid is converted to acetic acid, added to coA to make acetyl coA
3. Krebs cycle
 in mitochondria acetyl coA undergoes a series of conversions where pairs of electrons
are removed and passed to an acceptor molecule….NAD or FAD
 FAD and NAD carry the electrons to the ETC to make ATP
4. ETC
 electrons removed from food molecules in processes 1, 2, 3 are passed along a series
of electron acceptors
 H is pumped across the mitochondrial membrane…gradient pulls it back in and ATP is
produced as these electrons move and their energy is captured
 O2 will accept some H to make H2O
Mechanisms of ATP Synthesis
 energy/electrons is freed up during cellular respiration and it is captured to make ATP
 this occurs in 2 different ways…substrate level phosphorylation and oxidative
phosphorylation
Substrate Level Phosphorylation
 high energy phosphates are transferred directly from phosphorylated substrates (such
as glyceraldehyde phosphate) to ADP
 the P bound to the other substrate is very unstable so it will find an ADP and bind to
that to be more stable
 this happens in glycolysis and krebs….produces a very small amount of ATP
Oxidative Phosphorylation:
 more complicated, but more ATP is created this way
 done by electron transport proteins
 energy released in oxidation of food is used to pump H+ protons across the
mitochondrial membrane to create a steep concentration gradient for protons across
the membrane through a membrane channel called ATP synthase…some of this
gradient energy is captured and used to attach phosphate to ADP
Sites of Cellular Respiration
glycolysis – cytoplasm
Krebs – mitochondria
Acetyl coA – mitochondria
ETC – mitochondria
Energy Sources for Cellular Respiration
CHO

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

starch, glycogen, disaccharides, simple sugars
can be used in glycolysis
can be stored as glycogen …..glycogenesis
stored glycogen can be converted back to glucose….glycogenolysis
can be stored as fat…when glycogen stores are full ….lipogenesis
can be made from glycerol, lactate, amino acids…gluconeogenesis




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
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mobilized from triglycerides (one type of fat) ….that are stored or eaten
TG splits into 3 fatty acids and glycerol
used for fuel…lipolysis
used for fuel if glucose levels are low
used for fuel if metabolic demands increase beyond what glucose can provide
used for fuel by liver, resting skeletal muscle, adipocytes
fatty acid converts to acetyl coA…enters krebs cycle, ETC….beta oxidation
glycerol enters glycolysis as glyceraldehyde……pyruvate…acetylcoA….Krebs…
LIPIDS
AMINO ACIDS
 body prefers to use them for protein synthesis
 can be used as energy if body has excess amino acids or if glucose and fat supply is
exhausted
 enters the pathway at Krebs cycle as pyruvic acid, acetyl coA and Krebs cycle
intermediates
 can be converted to fat….lipogenesis
 can be converted to new glucose….gluconeogenesis
Carbohydrate Metabolism




all CHO are transformed to glucose
glucose enters cells with the help of insulin
glucose can be used to make ATP (glycolysis)
glucose can be stored as glycogen (glycogenesis)
when glucose enters cells…..
 immediately phosphorylated to Glucose 6 Phosphate (G6P)
 a P is taken from an ATP molecule
 this can not be reversed, most cells lack the enzyme needed to reverse
this….therefore glucose is trapped inside the cells….and since G6P is different than
glucose…..intracellular glucose levels are therefore kept low (since it is immediately
converted to G6P)….this maintains a gradient for
glucose to enter the
cells…..good thing (intestine, kidney and liver can
reverse this process)
 glucose can continue on the glycolysis path or convert to glycogen for storage
Glycolysis





series of 10 chemical reactions
occurs in the cytoplasm
glucose is converted to 2 pyruvic acid molecules
one 6 carbon molecule is converted to two 3 carbon molecules
anaerobic process…does not use oxygen…will occur in the presence or ansence of
oxygen
3 major phases
1. Activation of Sugar
2. Cleavage of Sugar
3. Oxidation and ATP Synthesis
final product = 2 molecules of pyruvic acid
1. Sugar Activation
 glucose is phosphorylated to Glucose-6-Phosphate (G6P)
 G6P changes to Fructose-6-Phoshate (F6P)
 F6P is phosphorylated to F-1,6-Bisphosphate
 2 ATP used for those 3 steps….each time a P is added…..uses and ATP
2. Sugar Cleavage
 F-1,6-Bisphosphate splits into two 3C molecules (G3P) or (DHP)
(glyceraldehyde 3 phosphate or dihydroxyacetone Phosphate)
3. Oxidation and ATP Synthesis
 six steps
 the two G3P are oxidized…2H+ is removed from each….picked up by 2NAD+
 P is then attached to each G3P
 later the P are cleaved off and 4 ATP are created
final product is:
 2 pyruvic acid
 2 NAD that picked up 2H+ each….they are reduced to NADH2
 2 ATP molecules (2 were used in phase 1, 4 were made in phase 3)
glucose was C6H12O6
pyruvate is C3H4O3 and C3H4O3 so……4 H missing……bound to NAD
Products of Glycolysis
ATP
 4 are produced…step 7 and step 10
 2 were used….step 1 and step 3
 net production = 2 ATP
NADH2
 2 NADH2 are made …step 6
 if O2 present……NADH2 will carry those H to ETC…..in ETC….each will produce 2
ATP
 if O2 no O2 present…..NADH2 will offload these H onto the pyruvic acid….makes
lactic acid
PYRUVIC ACID
 2 are produced
 if no O2 present…..converts to lactic acid…..takes the H from the NADH2
 lactic acid leaves the cell, enters blood, travels to liver to be reconverted to glucose
(gluconeogenesis)
 the freed up NAD can pick up more H as glucose is being broken down so that
glycolysis can continue
 ** no O2 situation…strenuous exercise….need to make O2 fast….need glycolysis so
to make ATP fast……need to have NAD to pick up the H and then need to dump the H
off somewhere and need to pick up more. If O2 was present, the NADH2 could dump
the H in the ETC (because the H would combine with the O2 to make H2O)…but no
O2 avail so NADH2 dumps the H onto pyruvic acid and is free and glycolysis can
continue.
 If O2 present, pyruvic acid is converted to acetyl coA and it enters the krebs
cycle……and the NADH2 enters the ETC
Functions of Glycolysis
1. produce ATP
2. produce pyruvic acid for oxidation in mitochondria
3. release H to be used for production of ATP in the ETC
Specific Reactions
Activation of Sugars
1.
2.
3.
glucose (6C)
ATP needed to add a P
glucose-6-phosphate (6C-P)
changes structure
fructose-6-phosphate (6C-P)
ATP needed to add a P
fructose-1,6-bisphosphate (P-6C-P)
Splitting of Sugars
4.
fructose-1,6-bisphosphate (P-6C-P)
sugar splits into 2
glyceraldehyde-3-phosphate (3C-P)
dihydroxyacetone phosphate (P-3C)
Oxidation reactions
5.
6.
7.
glyceraldehyde 3-phosphate (3C-P)
2H+ removed, picked up by NAD
to form NADH2 to go to ETC
1,3-bisphosphoglycerate (P-3C-P)
phosphate removed to create ATP
3-phosphoglycerate (3C-P)
changes structure
glyceraldehyde 3-phosphate (3C-P)
2H+ removed, picked up by NAD
to form NADH2 to go to ETC
1,3-bisphosphoglycerate (P-3C-P)
phosphate removed to create ATP
3-phosphoglycerate (3C-P)
changes structure
8.
9.
2-phosphoglycerate (3C-P)
2-phosphoglycerate (3C-P)
changes structure
phosphoenolpyruvate (3C-P)
phosphate removed to create ATP
pyruvate (3C)
changes structure
phosphoenolpyruvate (3C-P)
phosphate removed to create ATP
pyruvate (3C)
Activation of Sugars
1.
2.
3.
glucose (6C)
ATP needed to add a P
glucose-6-phosphate (6C-P)
changes structure
fructose-6-phosphate (6C-P)
ATP needed to add a P
fructose-1,6-bisphosphate (P-6C-P)
Splitting of Sugars
4.
fructose-1,6-bisphosphate (P-6C-P)
sugar splits into 2
glyceraldehyde-3-phosphate (3C-P)
dihydroxyacetone phosphate (P-3C)
Oxidation reactions
5.
6.
7.
8.
9.
glyceraldehyde 3-phosphate (3C-P)
2H+ removed, picked up by NAD
to form NADH2 to go to ETC
1,3-bisphosphoglycerate (P-3C-P)
phosphate removed to create ATP
3-phosphoglycerate (3C-P)
changes structure
2-phosphoglycerate (3C-P)
changes structure
phosphoenolpyruvate (3C-P)
phosphate removed to create ATP
pyruvate (3C)
glyceraldehyde 3-phosphate (3C-P)
2H+ removed, picked up by NAD
to form NADH2 to go to ETC
1,3-bisphosphoglycerate (P-3C-P)
phosphate removed to create ATP
3-phosphoglycerate (3C-P)
changes structure
2-phosphoglycerate (3C-P)
changes structure
phosphoenolpyruvate (3C-P)
phosphate removed to create ATP
pyruvate (3C)
Activation of Sugars
1. ATP needed to add a P………………..…………1 ATP used
2. changes structure
3. ATP needed to add a P……………………………1 ATP used
Splitting of Sugars
4. sugar splits into 2
Oxidation reactions
5. NADH2 made ……………………………………… 1 NADH2 made
NADH2 made ……………………………..………...1 NADH2 made
6. phosphate removed to create ATP………………..1 ATP made
phosphate removed to create ATP…………………1 ATP made
7. changes structure
changes structure
8. changes shape
changes shape
9. phosphate removed to create ATP…………………..1 ATP made
phosphate removed to create ATP…………………..1 ATP made
total……
2 ATP used
2 NADH2 made
4 ATP made
so the story so far……………..






1 molecule of glucose broken down
2 ATP used to add P to glucose
glucose modified several times
glucose splits
phosphate is removed and 2 ATP are made
hydrogen is removed and picked up by NAD to make 2 NADH2 to go to ETC (if O2 is
present) to make ATP
 glucose is modified several more times
 phosphate is removed and 2 ATP are made
 2 pyruvic acid molecules are made
Fate of Pyruvic Acid
Aerobic vs. Anaerobic conditions
1. If no O2 present…..Anaerobic conditions
pyruvate is converted to lactic acid
 the H+ removed during glycolysis that was picked up by NAD is released from NAD
and reattached to the pyruvate to form lactic acid
 the lactic acid leaves the cell, enters the blood
 taken to the liver for gluconeogenesis…..convert into glucose
why does this happen?
 to use glucose for fuel, a few conditions must exist……
2 ATP available for initial few steps
NAD available to pick up the H
4 ADP available to pick up P to make ATP
 NADH2 needs to dump its hydrogen off in order to be available to pick up more during
the process of glycolysis
 ideally…..O2 would be available and that 2H would combine with the O2 to make H2O
 but……..anaerobic conditions….no O2 available…ie. strenuous exercise……burning
glucose…it is a quick and easy fuel to use. Fat and amino acid burning needs O2
 no O2 available so……the pyruvic acid can accept the H to allow the process to
continue without O2
 the NAD are now freed up to accept more H and more glucose can breakdown for fuel
2. If O2 present
pyruvic acid is converted to acetyl coA
 the NADH2 can take that hydrogen to the mitochondrial membrane and dump it off so
that it can eventually combine to the O2 to make H20.
 the freed up NAD can return to glycolysis to pick up more H
 since the pyruvic acid does not need to pick up the H+, it wont change to lactic acid
 the pyruvic acid will continue on the oxidative pathway.
 the pyruvic acid enters the mitochondria and forms acetyl coA
Krebs Cycle and ETC
so the story so far………Glycolysis……..
 1 molecule of glucose broken down
 2 ATP used to add P to glucose
 glucose modified several times, glucose splits
 phosphate is removed and 2 ATP are made
 hydrogen is removed and picked up by NAD to make 2 NADH2 to go to ETC (if O2 is
present) to make ATP
 more phosphate is added
 glucose is modified several more times
 phosphate is removed and 2 ATP are made
 2 pyruvic acid molecules are made
Fate of Pyruvic Acid
1. If no O2 present…..Anaerobic conditions…pyruvate is converted to lactic acid
 the H+ removed during glycolysis that was picked up by NAD is released from NAD
and reattached to the pyruvate to form lactic acid
 NADH2 needs to dump its hydrogen off in order to be available to pick up more during
the process of glycolysis
 ideally…..O2 would be available and that 2H would combine with the O2 to make H2O
 but……..anaerobic conditions….no O2 available…ie. strenuous exercise……burning
glucose…it is a quick and easy fuel to use
 no O2 available so……the pyruvic acid can accept the H to allow the process to
continue without O2
 the NAD are now freed up to accept more H and more glucose can breakdown for fuel
2. If O2 present
pyruvic acid is converted to acetyl coA
 the NADH2 can take that hydrogen to the mitochondrial membrane and dump it off so
that it can eventually combine to the O2 to make H20.
 the freed up NAD can return to glycolysis to pick up more H
 since the pyruvic acid does not need to pick up the H+, it wont change to lactic acid
 the pyruvic acid will continue on the oxidative pathway.
KREBS CYCLE
Formation of Acetyl CoA
 occurs in mitochondria if O2 is available
 pyruvate enters mitochondrial matrix and is converted to acetyl coA
 in that process, a carbon is removed…released as CO2 and 2H are removed….picked
up by NAD…..taken to ETC…
 acetic acid is result, coenzyme A joins acetic acid….forms acetyl coA
 recall…..2 pyruvate molecules made….therefore each undergoes change to acetly coA
and each produces a NADH2
so………the story so far………………..
Glycolysis
2 ATP used
2 NADH2 made
4 ATP made
2 pyruvic acid molecules made
Acetyl coA formation
2 NADH2 made
Krebs Cycle
 Acetyl CoA enters Krebs cycle
 the CoA takes the 2 carbon acetic acid to combine it with 4 carbon oxaloacetic acid to
make 6 carbon citric acid
 citric acid enters cycle…8 reactions which rearrange the molecule…carbons removed,
hydrogens removed
 acetic acid is completely gone by the end of the cycle and the oxaloacetic acid is ready
to pick up another acetic acid
 what is made…..2 CO2, 3NADH2, 1FADH2, 1ATP
each pyruvic acid yields…..
1 CO2 …….in acetyl CoA formation
2 CO2 …….in krebs
1NADH2 ….in acetyl CoA formation
3NADH2 … in krebs
1 FADH2 … in krebs
1ATP
recall……2 pyruvic acid molecules come from one glucose
so…..
2NADH2 from acetyl coA
6NADH2 from krebs
2FADH2 from krebs
2ATP from krebs
Electron Transport Chain and Oxidative Phoshorylation
 the H removed during oxidation of food in glycolysis and krebs are combined with
oxygen and the energy released during those reactions is harnessed to attach P to
ADP
 protein-metal complexes in the mitochondrial membrane are alternately reduced and
oxidized by picking up electrons and passing them on to the next complex in sequence
 the first complex accepts H from NADH2…oxidizing it to NAD
 FADH2 transfers its H further along
 the H splits into its protons and electrons
 the electrons are shuttled along the membrane from one acceptor to the next, the
shuttling of electrons provides energy to pump protons out to the intermemb space
 the protons escape into the matrix and then are sent across the membrane into the
intramembrane space
 the electrons are delivered to O2 to create H2O
 the proton movement creates a gradient (proton motive force) that is higher in the
intramembrane space than in the matrix and it creates a voltage gradient that is
positive in the intramembrane space and negative in the matrix
 these conditions strongly attract H+ back into the matrix
 H+ cannot cross the membrane …impermeable
 enzyme-protein complex/carrier…..ATP synthase is freely permeable to H+
 protons go through here…create an electrical current and ATP synthase harnesses
this electrical energy to attach a P to ADP to form ATP
 the H combines with the electrons and O2 to make H2P
Total ATP Production
one molecule of glucose……..
 4ATP from substrate level …….2 glycolysis, 2 krebs
 each NADH transfering 2H to ETC contributes enough energy to the proton gradient to
generate 3 ATP
 each FADH2 transfers 2H to ETC a little father along…..generates 2 ATP
2 NADH from glycolysis…….6 ATP
8 NADH from krebs…………24 ATP
2 FADH from krebs…………..4 ATP
…….38ATP
but…..the 2NADH formed in glycolysis……in cytoplasm….outside membrane……cant cross the
membrane…….needs ATP to carry each across
so…….deduct 2 ATP……total = 36
Again……
glycolysis
2 ATP made …………………………….…….….2 ATP
2 NADH2 made ……………………….……….…4 ATP
acetyl coA formation
2 NADH2 made ……………………….………….6 ATP
krebs
2 ATP made………………………………………. 2 ATP
6NADH2 made ……………………………………18 ATP
2 FADH2 made ……………………………………4 ATP
36 ATP total
Other Metabolic Processes
glycolysis - use glucose to make ATP
glycogenesis - make glycogen
glycogenolysis - breakdown glycogen
gluconeogenesis - making glucose from noncarbohydrates
lipolysis (beta oxidation and glycerol breakdown)– breakdown fat
lipogenesis - make fat
Glycogenesis
 excess consumption of glucose doe not lead to unlimited ATP production
 cant store large amounts of ATP
 rising ATP levels In cells inhibits glycolysis and initiates the storage of glucose
 we store glucose as glycogen or fat….body can store more fat than glycogen
 Glycogenesis = making glycogen
 from glucose
 when ATP levels are high…don’t need to make more…..dont need to break down the
glucose to make more ATP
 glucose enters cells from blood
 ATP used to add P…..this forms glucose-6-phosphate
 glucose-6-phosphate changes to glucose-1-phosphate
 phosphate is removed as Glycogen Synthase attaches the glucose to the growing
glycogen chain
 this happens in liver and muscle cells
so………..
glucose in blood…need to make ATP……….glycolysis……make ATP
excess glucose in blood…don’t need more ATP….glycogenesis…make glycogen
Glycogenolysis
 when blood glucose is low
 breakdown glycogen and change it into glucose
 glycogen phosphorylase cleaves a glycogen off the chain and adds a phosphate to
change it to glucose-1-phosphate
 this is then converted to glucose-6-phosphate
 enters glycolysis
 liver and kidney cells have glucose-6-phosphatase……removes the phosphate and
turns it into glucose….glucose can enter the blood….therefore the liver can do this and
can provide blood glucose for other organs to use when blood sugar levels drop
Gluconeogenesis
 making glucose from non-CHO…glycerol, amino acids, lactic acid
 in liver
 when dietary glucose is low, and when glucose reserves are depleted, and when blood
glucose is dropping
 glycerol and fatty acids…glycolysis processe reverses….glycerol and fatty acids enter
glycolysis and krebs (as G3P, and acetyl coA)
 lactic acid…Cori-cycle in liver, lactic acid is changed to glucose
 delivered to muscle and other organs
 during exercise or starvation
 in muscle, lactic acid is made, enters blood, to liver, enters liver cells, changes to
pyruvic acid (the 2H removed), pyruvate goes through reverse glycolysis, gets to G-6P….needs glucose-6-phosphatase to remove the P and convert to glucose
 free glucose enters blood, travels to muscles
Lipid Metabolism
Oxidation of Glycerol and Fatty Acids
 eat fat/triglycerides….they are made of glycerol and fatty acids
 when glucose levels are low triglycerides will be used as energy, also used if increased
metabolic demands are placed on the body
Lipolysis
 triglyceride split into glycerol and fatty acids
Glycerol Metabolism
 glycerol converts easily to glyceraldehyde phosphate…glycolysis intermediate
 one glyceraldehyde molecule will produce about ½ the amount that a glucose
will……18ATP
 recall one G3P in glycolysis will make:
1NADH2, 2 ATP, pyruvic acid
 pyruvic acid enters krebs:
1NADH2 in conversion to acetyl coA
3 NADH2 and 1 FADH2 , 1 ATP
 total……19ATP
Beta Oxidation
 initial phase of fatty acid oxidation, in mitochondria
 fatty acid chains are broken into 2 carbon acetyl CoA fragments
 to the long fatty acid chain…
 CoA is added, ATP is used to add a P, 2FADH2 made, 2NADH2 made
 the 2 end carbons (alpha and beta) are removed as acetyl CoA…enters krebs
 recall..…from acetyl CoA....3 NADH2, 1 FADH2 and 1 ATP made
 so a 2 carbon fatty acid fragment makes:
1 FADH2……………2 ATP
1 NADH2……………3 ATP
3 NADH2 (acetyl coA in krebs)………9 ATP
1 FADH2 (acetyl coA in krebs) ………2 ATP
1 ATP (acetyl coA in kebs)……………1 ATP
 so… lipids can produce tons of ATP
 since: 2 carbons of a fatty acid/acetyl coA makes 17 ATP
each fatty acid can be 18 carbons long…..9 acetyl CoA
3 fatty acids make a triglyceride……27 acetyl CoA
glycerol makes 19 ATP
 but……
fat stores are harder to access, can’t provide ATP quickly
so if start exercising….switch to glucose burning……access it fast
 the glycerol changes to glyceraldehyde……can be used for gluconeogenesis since
that reaction can be reversed
 the fatty acids change to acetic acid….can not be used for gluconeogenesis since the
reaction is not reversible past pyruvic acid
Lipogenesis
 when glycerol and fatty acids are eaten, if not needed immediately for energy, they are
recombined into triglycerides and stored
 if cellular ATP and glucose levels are high…..dont need to break down fat
 excess ATP leads to accumulation of acetyl coA and G3P since you don’t need to use
them to make more ATP….dont need glycolysis (G3P) or krebs (acetyl coA) to occur
 Acetyl coA molecules join together to make fatty acid chains
 glucose therefore is easily converted to fat……goes through glycolysis…to
pyruvate……to acetyl coA……if too much or too much ATP…..acetyl coA to fatty acid
 G3P changes to glycerol….added to the fatty acids….makes TG
Amino Acid Metabolism
Protein Metabolism
 eat protein…into blood…into cells to replace tissue proteins
 excess protein eaten and available…use for energy or convert to fat
Oxidation of Amino Acids
 amino acids must be deaminated…amine group NH2 removed
 then converted to pyruvic acid or a keto acid in krebs
1. Transamination
 transfer of amine group to alpha ketoglutaric acid (a krebs intermediate)
 the original amino acid is now a keto acid (used as a krebs intermediate)
 the keto acid is now glutamic acid (an amino acid)
2. Oxidative Deamination
 in liver
 amine group on glutamic acid is removed as ammonia (NH3) and alpha
ketoglutaric acid is regenerated (used as a krebs intermediate)
 liberated NH3 is combined with CO2 to make urea and water
 urea to blood to urine
3. Keto Acid modification
 keto acids resulting from transamination is altered to produce molecules
to enter krebs…pyruvic acid, acetyl CoA, alpha ketoglutaric acid,
oxaloacetic acid
deaminated amino acids can convert to pyruvate and be reconverted to glucose
and contribute to gluconeogenesis
Thermoregulation






maintenance of a constant internal temperature
balance between heat production and heat loss
temp 36.5 to 37.5 celsius is ideal, maintained between 35.8-38.2
core temp is precisely regulated
blood is the heat exchange regulator between core and shell
if shell is warmer than environment….lose heat from body as warm blood flows through
skin capillaries
 if shell is colder than environment….must conserve the heat in body….blood bypasses
the skin…reduces heat loss, allows shell temp to fall toward environment temp
Metabolic Rate
 body’s rate of energy output
 heat produced by all the chemical reactions and mechanical work of the body
BMR
 a standardized measure of metabolic rate in a relaxed state
 energy needed to perform most essential activities
 70kg adult approx 60-72 kcal/hr for 70kg person
Factors Affecting MR
 body surface area…increased surface area = increased BMR
 age…young = higher BMR….need for growth, more muscle tissue
 gender…males = higher BMR…more muscle tissue
 stress…adrenaline released…..increases fat catabolism
 hormones…thyroid hormone, testosterone
Heat Exchange
 heat travels down gradient from warm to cold
1. radiation
 infrared waves radiate from body
 warm objects transfer heat to cool objects
2. conduction
 heat transfer through direct contact
3. convection
 warm air rises away from body and is replaced by cooler air
4. evaporation
 water evaporates because the water molecules absorb heat and become
energetic/vibrate fast enough to escape as gas (water vapor)
 water absorbs a lot of heat before vaporizing, when it evaporates it removes heat from
the body
insensible water loss
 evaporation from lungs, mucosa of mouth and skin…unnoticeable…insensible
sensible water loss
 when body temp rises and sweating increases
Role of Hypothalamus
 heat loss and heat promotion are integrated in the hypothalamus
 afferent impulses come from peripheral thermoreceptors in the skin/shell and from
central thermoreceptors in the blood vessels/core
 acts like a thermostat
 responds to signals to increase heat production or heat loss
Heat Promoting Mechanism
 external temp or blood temp is low
 response:
1. constriction of cutaneous blood vessels
 blood bypasses the skin and stays in the core
 skin is separated from the core by a layer of insulating fat….so heat in the core can not
escape and not much heat is lost from the shell since it is all in the core
 shell temp drops toward external temp…ok for a short time
2. shivering
 increased muscle tone occurs which stimulates stretch receptors in antagonist muscles
 this increases muscle activity….heat production
3. increase in metabolic rate
 epinephrine released by adrenals due to SNS stimulation…..stressful situation
 causes elevated metabolic rate which increases heat production
4. enhanced thyroxine release
 hypothalamus stimulates thyroid to release thyroid hormone
 mostly for the gradual temp change as seen in change of seasons
Heat Loss Mechanism
 protects the body from overheating
 when core temp rises above normal the heat promoting mechanisms in the
hypothalamus are inhibited and heat loss centre triggers:
1. dilation of cutaneous blood vessels
 the motor fibers that innervate skin blood vessels are inhibited so they dilate
 warm blood fills the blood vessels and as skin vessels are near the surface of the skin,
heat is lost by radiation, conduction, convection
2. enhanced sweating
 extremely overheated or if external temperature is so hot that heat cannot be lost by
other methods, evaporation is necessary
Vitamins




potent organic compounds, needed in minute amounts
for growth and good health, not used for energy
are crucial in helping the body use nutrients
most function as coenzymes, help enzymes accomplish chemical tasks
Water Soluble Vitamins
 B complex, C
 absorbed along with water in GI tract
 excess is excreted in urine in about an hour
Fat Soluble Vitamins
 A, D, E, K
 bind to ingested fats and are absorbed along with fat
 store in body….excess can lead to toxicity
B1 – thiamine
role: metabolism of pyruvic acid and other keto acids in CHO and protein metabolism,
helps with synthesis of ribose and deoxyribose, helps with synthesis of acetylcholine
(neurotransmitter)
deficiency: beriberi…polyneuritis, cardiac failure, GI disorders, lack of coordination
B2- riboflavin
role: coenzymes FAD, FMN, involved in oxidation of CHO and fat…oxidatic
phosphorylation
deficiency: epithelial and mucosal deterioration, photophobia, cheliosis, scaly dermatitis
at angles of nose, keratitis of cornea
B3 – niacin
role: coenzyme NAD, NADP, involved in oxidation of CHO and fat…oxidative
phosphorylation
deficiency: Pellegra - muscle weakness, poor gland secretion, diarrhea, dermatitis,
dementia
excess: megadose….hyperglycemia, vasodilation, tingling, liver damage
B5 - pantothenic acid
role: forms CoA…..needed to make acetyl CoA
deficiency: loss of appetite, depression, muscle spasms
B6- pyridoxine
role: involved in transamination, hemoglobin synthesis, glycogenesis
deficiency: seizures, dermatitis, nausea
B7 – Biotin
role: forms several enzymes for CHO, fat, pro metabolism, fatty acid synthesis, amino
acid synthesis, glycogen synthesis, growth of hair, skin, oil glands, red blood cells
deficiency: dermatitis, tongue soreness, anemia, depression
B9 - Folic Acid
role: synthesis of amino acids, DNA, cell growth, reproduction, dvmt of neural tube
deficiency: anemia, impairement of cell division, diarrhea, neural tube defects
B12 - cyanocobalmin
role: formation, growth and maturation of RBCs
deficiency: pernicious anemia = megaloblastic anemia…..RBCs get huge, lack DNA to
divide, huge RBCs cant leave the bone marrow, so circulating RBC levels are low
C - ascorbic acid
role: antioxidant, connective tissue/collagen formation, resistance to infection, role in
growth of connective tissue, bone, teeth, role in wound and bone healing
deficiency: poor healing, poor tooth and bone growth, scurvey
Fat Soluble Vitamins
A - retinol
role: growth, development of eye pigments/photoreceptors, integrity of skin and mucosa
deficiency: blindness, epithelia changes, dry skin, dry eyes, cloudy cornea
excess: nausea, vomiting, hair loss, joint pain etc.
D – calciferol
role: aids calcium absorption from GI and deposits it in bone, for blood clotting, bone formation
deficiency: faulty bone mineralilzation…weak bones, rickets…..children, osteomalacia in
adults…weak, soft bones
excess: nausea, vomiting, cardiac and renal damage
E – tocopherol
role: antioxidant, prevents oxidation of unsaturated fatty acids, neutralizes free radicals –
prevents damage to cell membranes
deficiency: hemolysis of blood cells, fragile capillaries
excess: slow wound healing, increased clotting time
K
role: blood clotting
deficiency: bruising