Download Matter + Energy

Physiology and the Principles of Physiology
What is a physiological system? Matter + Energy
Matter
Occupies space
-Solid, liquid, gas
In human solid = bone, muscle, skin
liquid = blood, saliva, urine
gas = air breathed
Energy
Capacity to do work
1. Kinetic = energy used to produce work
2. Potential = stored energy, not currently being
used to produce work.
A physiological system must have both
matter and energy.
Forms of Energy
a. Chemical--stored in chemical bonds;
concentration differences
b. Electrical--charged particles; ions
c. Mechanical--directly moving object
d. Radiant--travels in waves
e. Thermal--molecular movement
Composition of Matter
1. Atoms
a. Nucleus
1) Protons: +charge
2) Neutrons: 0 charge
b. Electrons: -charge
Atomic Number
Number of protons of nucleus
1H
= hydrogen
2He = helium
Neutral atom; protons = electrons
Mass Number
Sum of masses of protons and neutrons
Hydrogen = 1proton 0 neutron = mass# = 1
Helium = 2 p 2 n = mass# = 4
Elements
-Elements are substances that cannot be broken
down into simpler substances
(Ex: H, C, O)
-The number of protons, neutrons, and electrons
differs between elements
Combining of Elements
1.  Molecule--2 or more atoms of the SAME element
If elements are the same, then have
molecule of that element.
Molecular O2 vs elemental O
2. Compound--2 or more different elements
NaCl, H2O
Breakage of bonds--provide energy to move
matter
Mixtures – 3 forms
1) Solutions- Homogenous mixtures
of 2 or more substances
a.  Solvent = substance in greatest quantity
(H2O)
b. Solute = substance in smaller quantity
(ions, proteins, carbohydrates, etc.)
These systems also contain matter, energy
Concentrations of Solutions
1) Percent--parts/hundred parts
10% solution NaCl = 10 p NaCl/100 p H20
2) Molarity--moles/liter
1 mole of any element/cmpd = molecular weight
(sum of atomic weights) in grams.
C6H12O6
C 6x12.011= 72.066
H 12x1.008= 12.096
O 6x15.999= 95.994
Total: 180.156g or 1M
1M solution = 1M of a chemical substance in 1L
of solvent
1M of any substance always contains the exact
# of solute particles...
Avogadro’s Number: 6.02x10^23
1M Glucose: 180g
1M Water: 18g
1M Methane: 16g
…You will always have 6.02x10^23 molecules
of that substance
3) Osmolarity/Osmolality
Number of particles within a solution
Membrane-semipermeable
Important in controlling movement of fluids between
body compartments. Differences in osmolality between
compartments serves as energy.
Mixtures contd…
2) Colloids--solute is large, but dissolvable,
particles scatter light.
(Jello, cell cytoplasm)
3) Suspensions--mixtures of solutions where
the solute will settle out unless you
repeatedly shake it.
(Sand in water, blood cells in plasma)
Chemical Bonds
Combination of atoms via electron sharing
Electron shell--electrons exist in different regions
around nucleus.
Each shell = different level of energy
Close to nucleus =
lower energy.
Each shell can hold a specific # of electron…
Lowest energy level
accepts 2 electrons.
2nd level accepts 8
3rd level accepts 18
Valence shell--outermost shell of that given atom.
Electrons here can be reactive, and can form chemical
bonds with one another.
If the valence shell is “full”, then the atom is
not reactive.
“Full” = 2 electrons in
lowest energy level.
8 electrons in 2nd
level
If the valence shell is not full, then the atom is reactive
These atoms are very
prevalent in
physiology
Energy is
transferred during
reactions between
these atoms.
Bonds are formed
Types of Chemical Bonds
1) Ionic bonds--one atom donates electron
to the electron shell of another atom
Anion (acceptor) and cation (donor)
End result is stable valences for both
2) Covalent bond-electrons are shared
between two atoms
-Electron sharing-equal or unequal
a) non-polar--equal
sharing (CH4)
b) polar--unequal
sharing
(H2O)
3) Hydrogen bonds-attractions between slightly
charged molecules such as
water
Chemical Reactions
1. Equations
4H + C → CH4
2.
a.
b.
c.
Patterns of chemical reactions
Synthesis
A + B → AB
Decomposition
AB → A + B
Exchange
AB + C → AC + B
Exergonic--give off energy
Ex: Breakdown of a glucose molecule
Endergonic--absorb energy
Ex: Formation of ATP
Reversibility of Chemical Reactions
A+B
→
C
A+B
Effectors of Chemical Reactions
a. Temperature--higher, faster rate
b. Particle size--larger or smaller
c. Concentration--greater, faster rate
d. Catalysts
1) enzymes--faster rate
↔
C
Part II- Biochemistry
In physiological systems we find inorganic and
organic compounds that:
-are reactive and interactive
-store and release energy
-are structurally strong
-are catalysts
Inorganic Compounds
1) Water
a. Heat properties-absorb or lose heat
b. Solvent properties-polarity
c. Reactivity
2) Salts--ionic
compounds with
cations other than H+
and anions other
than OH-
Electrolytes--ions;
conduct current in solution
NaCl, KCl
3) Acids and Bases
a. Acids
1) Sour
2) Dissolve in water (release protons)
3) Concentration of protons determine acidity
Ex: HCl
b. Bases
1) Bitter
2) Dissolve in water (release OH-)
3) Take on protons
Ex: HCO3-, NH3
pH-- acid/base
H+ concentration
logarithmic scale
pH is tightly
regulated--why?
Organic Compounds
1. Carbohydrates
Carbon + Hydrogen + Oxygen 1:2:1
1) Monosaccharide--one chain or ring; ribose,
glucose, fructose
2) Disaccharides--two rings joined; glucose +
fructose = sucrose
3) Polysaccharides--three or more sugars—
starch, cellulose, glycogen
Carbohydrate function--fuel
2) Lipids
Carbon + Hydrogen + Oxygen--proportion of O
is much lower than carbohydrates; also some
Phosphorus
Neutral fats--triglycerides
1) glycerol--3 carbon
2) fatty acids--long carbon chains
a) saturated--no C-C double bonds
b) unsaturated--at least one
C=C double bonds
Non-polar covalent bonds
Phospholipids--one fatty acid chain replaced
by phosphate group
Steroids--flat, 4 hydrocarbon rings
Cholesterol--membranes, bile salts, vitamin D
and steroid hormones (estrogen, testosterone)
3) Proteins
Carbon + Hydrogen + Oxygen + Nitrogen
Amino acids-- building blocks; 20
Polarity varies
Protein Structure
1) Primary structure--amino end of one amino
acid joins with acid end of second amino acid.
Forms peptide bond
2) Secondary
structure--α-helix,
β-sheet.
Folding of protein
due to amino acid
chain arrangement
3) Tertiary
structure--helix or
sheet folds over
itself
4) Quaternary
structure-aggregation of 2
or more
polypeptide
chains.
Hemoglobin
4) Nucleic Acids
C, H, O, N, P
2 major classes:
DNA--deoxyribonucleic acid; RNA--ribonucleic acid
Structural units: nucleotides
DNA
1) Location--nucleus &
mitochondrion
2) Structure--double
helix
3) Stability--stable
4) Function--template
for protein synthesis
5) Elements-sugar: deoxyribose
bases: A,T, C, G
phosphate
6) Complementary
bases; A:T; C:G
RNA
1) Location--outside nucleus
2) Structure--single stranded
3) Stability--easily broken down
4) Function--protein synthesis; messenger (mRNA),
ribosome (rRNA), amino acid carrier (tRNA)
5) Elements-a) sugar: ribose
b) bases: A, G, C, U (no Thymine)
6) Complementary bases A:U, G:C
Adenosine Triphosphate (ATP)--nucleotide with
3 additional phosphate groups
Energy--main energy currency for body