Download Carbohydrates (CHO) - Ms. Karellas

Welcome to Biology (SBI4U)
University Preparation
Teacher:
Email:
Website:
Ms. Karellas
[email protected]
karellas.weebly.com
Course Outline
Unit 1 - Biochemistry

Students will analyse the technological applications used in the food, pharmaceutical, and medical industries that affect
biological processes and cellular functions. They will investigate how molecules and their chemical properties affect
cellular processes and biochemical reactions. Students will demonstrate an understanding of the important structural
and functional roles compounds play in the cells of all living organisms.
Unit 2 - Metabolic Processes

Students will investigate the chemical changes and energy conversions that occur in metabolic processes. They will
demonstrate the ways in which an understanding of metabolic processes enables people to make informed choices
with respect to a range of personal, societal, and environmental issues.
Unit 3 - Molecular Genetics

Students will demonstrate an understanding that DNA contains all the genetic information for any living organism.
They will investigate how proteins control a wide variety of cellular processes. Students will assess the social, legal, and
ethical implications of genetic research and biotechnology.
Unit 4 - Homeostasis

Students will demonstrate an understanding of the strict limits on the internal conditions that organisms can tolerate.
The will investigate the ways in which organ systems that maintain homeostasis rely on feedback mechanisms. Student
will explore the environmental factors that affect homeostasis.
Unit 5 - Population Dynamics

Students will demonstrate an understanding of how population growth follows predictable patterns. They will
investigate how increased consumption of resources and production of waste is associated with population growth
and results in specific stresses that affect Earth's sustainability. Students will assess technological developments that
can contribute to or help offset the ecological footprint associated with population growth and the consumption of
natural resources.
Unit 1: Biochemistry
Introduction to Biochemistry:
https://www.youtube.com/watch?v=tpBAmzQ_pUE








Prior understanding
Elements are pure substances that cannot be broken down through
chemical or physical methods, elements consist of only one type of atom,
an atom is the smallest component of an element that retains the
properties of that element
A compound is a pure substance composed of two or more elements
chemically combined, there is a specific ratio of types of atoms
Atoms contain a nucleus with protons and neutrons, protons are
positively charged and neutrons have no charge
The number of protons defines the element i.e. Carbon has 6 protons
Negatively charged electrons travel in orbits (energy levels) around the
nucleus, loss or gain of an electron causes the formation of a charged ion,
electrons in the outer orbits are referred to as valence electrons,
negatively charged ions are anions, positively charged ions are cations
The number of electrons in an uncharged atom is the same as the
number of protons
The number of protons and neutrons determines the mass number of the
element i.e. Carbon – 12 has 6 protons and 6 neutrons
Complete the Diagnostic
Lesson 1:
Chemistry in Living Systems
What is biochemistry?
BRAINSTORM

Biochemistry: the branch of science
dealing with the chemical and
physiochemical processes that occur
within living organisms.
Organic Chemistry
What is the difference between organic and
inorganic molecules?
Organic molecules
– usually contain CARBON and
HYDROGEN
Inorganic molecules
– usually do not contain CARBON
Isotopes
elements that contain atoms with the
same number of protons but different
numbers of neutrons
 the atomic number remains the same, the
mass number changes

C-12 has a mass #12, 6 protons and 6 neutrons
 C-13 has a mass # 13, 6 protons and 7 neutrons
 C-14 has a mass # 14, 6 protons and 8 neutrons

C-12 makes up 99% of the carbon in
nature, C-14 is a radioisotope that breaks
down to release N-14, subatomic particles
and energy
 Radioisotopes decay in a predictable
manner called the half-life (time taken for
one half of the nuclei to decay)


Organisms take in radioactive carbon dioxide from
the environment until the day they die but over
time the radioactive carbon will decay but nonradioactive carbon will remain the same so the
ratio of radioactive carbon to non-radioactive
carbon can be used to date a specimen
Organic Elements and Bonding
electrons occupy volumes of space around the nucleus
called orbitals or energy levels
 2 electrons occupy the first energy level (1s orbital),
8 electrons occupy the second energy level (2 in a 2s
orbital, 6 in a 2p orbital)
 the outermost s and p orbitals are valence orbitals, and
the electrons in them are called valence electrons
 the chemical behavior of elements is determined by
these valence electrons

Organic Elements and Bonding
Atoms combine to make molecules.
 The bonds between atoms of the same
molecule (i.e. within the molecule) are
intramolecular bonds.

DEMO 
Organic Elements and Bonding
The three types of intramolecular bonds are:
1)
2)
3)
Non-Polar Covalent Bonds
Polar Covalent Bonds
Ionic Bonds
1. Non-Polar Covalent Bonds
Bond formed by sharing a pair
of valence electrons between
two atoms.
2. Polar Covalent Bonds
Bond formed by unequal sharing of a pair
of valence electrons between two
atoms.
One atom is slightly negative; one is
slightly positive (dipole)
3. Ionic Bonds
Bond formed by transfer of electrons
from atom to atom.
This results in the formation of positive
cation, and negative anion. Ions are held
together by electrostatic attraction.
Ions are important in living systems:
H+ ions are important in cellular respiration
 Na+ ions are part of transport mechanisms
that enable molecules to enter cells
 Ca+ ions are involved in nerve transmission

The Role of Electronegativity
Electronegativity is a measure of an
atoms ability to attract a shared
electron pair in a covalent bond
 Each element in the periodic table has an
assigned electronegativity number (EN) the larger the number, the greater the
greater the pull on the electron pair
 The element with the greater EN has a
partial (δ-) charge, the element with the
smaller EN has a partial (δ+) charge

∆En is the difference between the
electronegativity number between two
atoms participating in a covalent bond
 Electronegativity values can be found on a
periodic table.

Electronegativity difference
determines the BOND TYPE:
 ∆En = 0 is when atoms share electrons
equally, nonpolar covalent
 ∆En > 0 < 1.7 – one atom attracts the
electrons more than the other, polar
covalent bond
 ∆En > 1.7 or = 1.7 – electrons are
gained by one atom, lost by the other,
(anions and cations), ionic bond
∆En
∆En
∆En
0 ---0.5--------------> 1.7 ---------------> 4.2
Non-polar
polar covalent
ionic
EXAMPLE:
Bonds in Water (H2O)
Oxygen electronegativity = 3.44
Hydrogen electronegativity = 2.2
Difference 3.44 – 2.2 = 1.24
Bond Type  Polar covalent
 In a water molecule the oxygen is slightly
negatively charged because it has a higher
electronegativity
Learning Check!
Determine the type of bond:
a) KCl
b) CH4
c) H2
Learning Check!
Determine the type of bond:
a) KCl
K – 0.9
Cl – 2.9
2.9 – 0.9 = 2.0 ionic bond
b) CH4
C – 2.5
H – 2.1
2.5 – 2.1 = 0.4 non-polar covalent
c) H2
H – 2.1
2.1 – 2.1 = 0 nonpolar covalent
Organic Elements and Bonding
The bonds between molecule
intermolecular bonds.
 Weaker than intramolecular bonds
DEMO 


Two types of intermolecular interactions
are particularly important for biological
system: hydrogen bonding and hydrophobic
interactions
Hydrogen bonding:
water is a polar molecule, attractions
between (+) ends and (-) ends are called
hydrogen bonds (see role of water)

FON
Hydrophobic interactions: non-polar
molecules such as cooking oil and motor oil
do not form hydrogen bonds, but in the
presence of polar molecules such as water,
they tend to clump together, extruding
water.
 These are referred to as hydrophobic
(water fearing)
 Polar molecules that form hydrogen bonds
with water are said to be hydrophilic
(water loving)
DEMO 

Why is WATER a special molecule?
◦ Greater than 2/3 of body mass is water, lungs 90%
water, bones 20% water, fat is 25% water
◦ Controls body temperature, lubricates joints, shock
absorber in brain and spinal cord and moisturizes
surfaces
◦ Polar covalent bonds and asymmetrical structure
creates a highly polar molecule
◦ Polarity of water allows it to form chemical bonds
with other molecules (adhesion), itself (cohesion)
and ions
∆En
∆En
∆En
0 ---0.5--------------> 1.7 ---------------> 4.2
Non-polar
polar covalent
ionic
Learning Check!
Determine the type of bond:
a) KCl
K – 0.9
Cl – 2.9
2.9 – 0.9 = 2.0 ionic bond
b) CH4
C – 2.5
H – 2.1
2.5 – 2.1 = 0.4 non-polar covalent
c) H2
H – 2.1
2.1 – 2.1 = 0 nonpolar covalent
POLAR vs. NON-POLAR BONDS
RECALL:
Intramolecular vs. Intermolecular bonds
Electronegativity
 Elements have varying electronegativity (EN):
i.e. how strongly an atom can attract electrons


Non-Polar Covalent Bonds: the atoms involved have similar electro
negativities, so the electrons are equally shared.
(ex. H-H, O-O, C-H)
Polar Covalent Bonds: the atoms involved have different electro
negativities, so there is unequal sharing of electrons. This results in a
separation of charge.
(ex. O-H)
∆En
∆En
∆En
0 ---0.5--------------> 1.7 ---------------> 4.2
Non-polar
polar covalent
ionic
POLAR vs. NON-POLAR MOLECULES
*Polar bonds ≠ Polar molecule
*Non-polar bonds ≠ Non-polar molecule
Polar Molecules
If the molecule is asymmetrical and has polar covalent bonds, the
molecule will also be polar (e.g. glucose)
These molecules are “hydrophilic” (water loving)
Non-Polar Molecules
Non polar molecules occur when a molecule has non-polar covalent
bonds (e.g. C-H backbone)
OR …
the polar covalent bonds are in a symmetrical arrangement (e.g.
CCl4)
These molecules are “hydrophobic” (water hating)
Practice Questions:
1.Do the following groups contain polar or non-polar bonds?
a)
-OH
b)
-COOH
c)
-NH2
d)
-PO4
e)
-CH2
2. Are the above groups hydrophobic or hydrophilic?
3. Are the following molecules polar or non-polar?
4. Why is this important for biology?
(e.g. glucose, phospholipids)
Practice Questions:
1.
Do the following groups contain polar or non-polar bonds?
a)
-OH (polar) (hydrophilic)
b)
-COOH (polar) (hydrophilic)
c)
-NH2 (polar) (hydrophilic)
d)
-PO4 (polar) (hydrophilic)
e)
-CH2 (non-polar) (hydrophobic)
2.
Are the above functional groups hydrophobic or hydrophilic?
3.
Are the following molecules polar or non-polar?
(polar)
4.
(non-polar)
Why is this important for biology?
(e.g. glucose, phospholipids)
Functional Groups
– (aka reactive clusters)

What are functional groups and why are
they important?
All the biological molecules we will be
studying have important functional
groups which determine their function
and interactions in cells

With the exception of a few molecules
(i.e. carbon dioxide) compounds
containing carbon are referred to as
organic compounds. The organic
molecules of importance to living
organisms can be classified into groups –
carbohydrates, lipids, proteins and nucleic
acids.
Carbon

4 valence electrons can form 4 covalent
bonds with other elements

attach to each other to form linear or
branched or ring structures and therefore
are the backbone of biological molecules

molecules with only carbon and hydrogen
are hydrocarbons, non-polar due to the
symmetrical arrangement of their bonds

other elements such as hydrogen, oxygen,
sulfur, nitrogen and phosphorus may also
attach to the carbon backbone to form
functional groups
Functional Groups
Group
Chemical Formula
Hydroxyl
-OH
Carboxyl
-COOH
Amino
-NH2
Sulfhydryl
-SH
Phosphate
-PO4
Carbonyl
-COH or -CO-
Structural Formula
Create Study Cards for each functional group to REVIEW and
ASSESS your learning of today’s lesson.
Macromolecules of Life
MINDS-ON:
Macromolecule Sorting Activity!
Get into groups of 4
 Go to a station set up around the lab benches
 Using your understanding of functional
groups, sort the following molecules into the
four categories of macromolecules
(carbohydrates, lipids, proteins, and nucleic
acids) – paste them on the sheet
 First group to finish (correctly) gets a prize!


Learning Goals:
Understand the structure and function of
carbohydrates
 Understand that monosaccharides are the
smallest structural unit of carbohydrates
 List and describe the 4 types of
carbohydrates: monosaccharides,
disaccharides, oligosaccharides,
polysaccharides
 Demonstrate condensation and hydrolysis
reactions for carbohydrates

Macromolecules of Life
What is a macromolecule?
 Macromolecules:
A large molecule (polymer) made of
many smaller structural units
(monomers) linked together
1)Carbohydrates
2)Lipids
3)Proteins
4)Nucleic Acids
Macromolecules are assembled and
disassembled in the same way:
Monomers  Polymer

(Condensation/Dehydration Synthesis Reaction)
anabolic reaction - large molecules are built
from small subunits
 energy is required
 Water is released

Macromolecules are assembled and
disassembled in the same way:
Polymer  Monomer

(Hydrolysis Reaction) – hydro -water; lysis -broken
catabolic reaction - large molecules are
broken down into small subunits
 energy is released
 Water is used

Carbohydrates
(CHO)
Carbohydrates (CHO)
What is the function of carbohydrates?
 Used
as sources of energy
-Glucose: primary source of energy
-Sucrose/Lactose: dietary sugars
 Building materials
 Cell surface markers for cell-to-cell
communication
Carbohydrates



Contain C, H, O in a 1:2:1 ratio
Formula: (CH2O)n (n = # of Carbons)
Sugar names end in –ose
Simple Carbohydrates:
- Monosaccharide and Disaccharide
Complex Carbohydrates
-Polysaccharide and Oligosaccharide
Simple Carbohydrates
Monosaccharides: the smallest structural
unit (monomer) of a carbohydrate
E.g. C6H12O6 : Glucose, Fructose, Galactose

Numbering the Carbons
• monosaccharides with the same chemical
formula but different arrangement of atoms
are called isomers
i.e. C6H12O6 is glucose, galactose and fructose
α-Glucose vs. β-Glucose
When a glucose molecule forms a six-carbon ring…
50% chance the -OH will be below the plane (alpha)
50% chance the -OH will be above the plane (beta)
Simple Carbohydrates

Disaccharides: composed of two
monosaccharides (monomers) joined through
a condensation reaction, forming a glycosidic
linkage (covalent bonds)
Glucose + Glucose = Maltose
Ex. Infant formula, Beer
- Glucose + Fructose = Sucrose
Ex. Sugar cane, Table Sugar
- Glucose + Galactose = Lactose
Ex. Milk
-

Disaccharides/Polysaccharides can be
broken down through a hydrolysis reaction
Complex Carbohydrates

-
Oligosaccharides
3-10 monosaccharides linked
glucose + galactose + fructose = Raffinose
Found in beans, peas, lentils, broccoli,
asparagus
*Humans lack enzymes to digest oligosaccharides
(causes bloating, cramps, gas)
Complex Carbohydrates
Polysaccharides
- > 10 monosaccharides linked
- Most are made up of hundreds of
monosaccharides bonded together
- Types:
1. Starch: glucose storage in plants
2. Glycogen: glucose storage in animals
3. Dietary Fiber: not used for energy
-Cellulose: structural support in plants
-Chitin: structural support in organisms

Starch
A starch molecule contains hundreds of
glucose molecules in either
i) branched chains: Amylopectin or
ii) unbranched (coiled) chains: Amylose

 Sources:
grains, dried beans, pasta, bread, potato
Glycosidic bonds in Starch
Coiled
Branched
Glycogen
Found in liver and skeletal muscles
 Many branch points allows for rapid break
down for glucose to be released and used
for energy

Dietary Fiber

Group of plant polysaccharides that are not
digested or absorbed in the human intestine;
structural

Fibers: Cellulose, Chitin
Cellulose
Structural support in plant cell walls
 Also used by humans in
wood for lumber and paper, cotton and
linen for clothing
 Straight chain polymer of β 1-4
glycosidic linkages

Chitin
Structure support - exoskeleton of
insects, crabs, lobsters, fungi cell wall
 Also used in medicine: contact lenses,
surgical thread

Homework:

Carbohydrates Worksheet
Have a great weekend! 
Lipids
Triglycerides, Phospholipids, Sterols
Lipids
Lipids:
-composed of carbon, hydrogen, and oxygen atoms
-higher proportion of non-polar C-H (high energy)
bonds makes lipids hydrophobic
What is the function of lipids?
 Provides long-term energy storage, cushions
organs, provides cell membrane structure, synthesis
of hormones

Four types:
1) Triglycerides (fats)
2) Phospholipids
3) Steroids
4) Waxes
Fatty Acids




The building block (monomer) of lipids
Chain of carbon atoms
Carboxyl group (-COOH) at alpha (α-) end
Methyl group (-CH3) at omega (ω-) end
ω
α
How are fatty acids characterized?
Based on:






Length of carbon chain
Saturation
Degree of Saturation
Location of double bonds
Hydrogenation
Orientation of hydrogen around double bond
Length of Carbon Chain
Length of carbon chain:
- Short-chain fatty acids (<8 carbons)
- Medium chain fatty acids (8-12 carbons)
- Long chain fatty acids (>12 carbons)

Saturation
Saturated fatty acids:
have only single bonds between C atoms
- contain maximum # of H atoms possible

Unsaturated fatty acids:
have one or more C-C double bonds
- fewer than maximum # of H atoms possible
- formed by removing H atoms from molecule

Degree of Saturation

Saturated fatty acid
o Single carbon-carbon atoms
o Solid at room temperature
o Examples?

Monounsaturated fatty acid
o 1 double bond
o Thick liquid at room temperature
o Examples?

Polyunsaturated fatty acid (must be obtained through diet)
o > 2 double bonds
o Liquid at room temperature
o Examples?
Location of double bonds
Omega number (where the 1st double
bond is located relative to the methyl-end)
Example: Omega-3 and Omega-6 fatty acids

1 2 3 4 5 6
1 2 3
Hydrogenation

Double bonds carry a slightly negative charge,
and can accept positively charged hydrogen
atoms to create a saturated fatty acid
Polyunsaturated fatty acid
H+ H+ H+ H+
Hydrogenated (saturated) fatty acid
Orientation of Hydrogen around Double Bond
Cis- double bond
Hydrogen atoms are on the same side of
the double bond
 Trans - double bond
Hydrogen atoms are on opposite sides
of double bond

Fatty acid deficiencies
Irritated & flaky skin
 Gastrointestinal problems
 Compromised immune system
 Slow growth in children
 Reproductive failure
 Neurological and visual problems

1)Triglycerides

Made up of 1 Glycerol and 3 Fatty Acids
ESTER BOND
Triglyceride

Saturated fatty acid
Mono-unsaturated fatty acid
Poly-unsaturated fatty acid
2)Phospholipids
Head is polar (hydrophilic) –
glycerol, phosphate, choline
Tail is non-polar (hydrophobic) –
fatty acids
In FOOD:
•Stabilizers in food
- Mayo and ice cream
- Phosphatidylcholine = lecithin
- Soy products
1 Glycerol + 2 fatty acids
+ polar phosphate group
+ choline group
In water…

Phospholipids form micelles
Roles:
•Plasma membrane
•Emulsifiers
3)Sterols/Steroids

Four fused carbon rings with many different
functional groups
Steroids can be synthesized in the
body
 Steroids can be obtained through diet
 from plants and animals
 only animals have cholesterol
(meat, eggs, fish, dairy products)
**NOT all sterols are cholesterol!**


Important Roles of Steroids
 Bile acids
 Precursor for the production of hormones
 Cholesterol – found in cellular membranes
(provides support and fluidity)
 In medicine – used to reduce inflammation,
skin ointments, found in inhalers to treat
asthma
 Anabolic Steroids (synthetic) – build muscle
mass in people who have cancer or AIDS
(misused by athletes!)
**Important for us because we build our steroid hormones out of cholesterol**
4)Waxes
Lipids that contain long-chain fatty-acids linked to
alcohols or carbon rings; solid at room temperature
 Produced in plants and animals

Roles:
- Cutin: produced by plants to form a water-resistant
coating of the surfaces of stems, leaves and fruit;
helps the plant conserve water
- Birds: produce waxy material (to keep their feathers
dry)
- Bees: make beeswax to make honeycombs
- Humans: earwax (protects the ear canal)
Negative Health Effects of Lipids

-
Heart disease
Cholesterol plaque deposits in the arteries of the
heart (narrowed arteries)
Cancer
Breast cancer and Prostate cancer
Association not as strong as between fat intake and
heart disease
- Dietary fat may promote cancer once it has arisen
(does not initiate it)

-

Obesity
- High fat food vs. high energy food (kcal from carbs)
Positive Health Effects of Lipids

Omega-3 Fats:
- Prevent blood clots
- Protect against irregular heartbeats
- Lowers blood pressure (especially for
people with hypertension and
atherosclerosis)
REVIEW: CARBS and LIPIDS

https://www.youtube.com/watch?v=H8WJ2KE
NlK0

Seatwork/Homework: Lipids Worksheet
Proteins
https://www.youtube.com/watch?v=H8WJ2KENlK0
Learning Goals
Understand the function of proteins
 Identify and describe the structural units of
proteins (amino acids)
 Describe and draw condensation and
hydrolysis reactions
 Describe the four levels of protein
structure
 Apply understanding of protein structure to
explain the process of denaturation

Proteins
What is the function of proteins?
Speed up chemical reactions (catalysts),
transport specific substances, provide
structure, carry cellular messages, fight
infection…and many more!
Proteins
Amino acids: the building blocks
(monomers) of proteins
 The body uses 20 different types of
amino acids to make proteins
 Consist of:

 Central carbon bonded to hydrogen
Amino group
Carboxylic group
R-group
***The R group determines the
FUNCTION of the protein***
Types of Amino Acids
Polar – prefer an aqueous (water)
environment; usually exposed on the surface
of the protein
 Non-polar – do not prefer aqueous
environment; usually make up the core of
the protein
 Electrically Charged – positively or
negatively charged; hydrophilic

Amino Acids

Classification of Amino Acids in Nutrition:
 8 Essential a.a.
- the body can NOT synthesize these
- must be obtained through diet
 12
Non-essential a.a.
- The body can synthesize these from
other sources
TOTAL: 20 a.a.
Proteins – The peptide bond
Proteins are formed
when amino acid
(monomers) are
linked together by
peptide bonds
 Proteins are broken
down into amino
acids by the addition
of water to break
peptide bonds

Proteins
Dipeptide – 2 amino acids linked by a
peptide bond
 Tripeptide – 3 amino acids linked by 2
peptide bonds

Levels of Protein
Structure
Primary
Secondary
Tertiary
Quaternary
Primary (1˚)Structure - Polypeptide
sequence of amino acids
(aa) = polypeptide chain
 Critical to final protein
structure and function
 Determines the chemical
and physical characteristics
of the protein


Sickle cell anemia – single error in aa
sequence  affects folding  rigid, sticky,
sickle-shaped red blood cells
Secondary (2˚) Structure – coils and folds
As amino acids are added to the
polypeptide chain, it starts to fold along
its length and hydrogen bonds form
between elements of the amino acid
backbone
 Common patterns:

 α- helix
 β-folded sheets

α-helix :
2
3
1
4
Ex. Fibrous proteins such as α-keratin in hair

β-sheet: two parts of polypeptide lie parallel to one
another
Ex. Proteins in silk used
by spiders to make webs
Tertiary (3˚) Structure
Strong forces of attraction and repulsion
between the polypeptide & its
environment force further folding into a
tertiary structure
 Interactions involve the R-groups:

 Hydrogen bonds – polar side chains
 Ionic bonds – charged side chains
 van der Waals forces – non-polar R groups
 Proline – natural kink (in α-helix or β-sheet)
 Disulfide bridge – covalent bond between sulfur
containing R groups
Strong stabilizer
Quaternary (4˚) Structure – the final shape

Two or more folded polypeptide subunits
come together to make a functional protein

Physical and chemical environmental factors
play a role (aq, pH, temp)

Example: Hemoglobin
Protein Folding

http://www.youtube.com/watch?v=Pjt1Q2
ZZVjA
Changes in 3D shape of protein

Caused by changes in :
 Temperature
 pH
 Ionic concentration
Protein Denaturation
• Useful: Gastrin digestive enzyme works in stomach
(low pH) and inactive in small intestine (high pH)
• Dangerous: Prolonged fever above 39C can
denature critical enzymes in brain  death
The body burns
Carbohydrates
Fat
Protein
Not exclusive. All burned at the same time but in different amounts, in that order.
Seatwork/Homework
oMacromolecule
Chart
(complete – carbs, lipids, proteins)
oQuiz
on TUES: Carbs, Lipids, Proteins