Transcript Carbohydrates - Cloudfront.net

Carbohydrates
CH2OH
H
O
H
OH
H
H
OH
HO
H
OH
Energy Molecules
Carbohydrates
Carbohydrates are composed of C, H, O
carbo - hydr - ate
CH2O
(CH
(CH
2O)
xx
2O)

H12
CC66H
12O6
6
Function:
u energy
u raw materials
u energy storage
ustructural materials

Monomer: sugars

ex: sugars, starches, cellulose
sugar sugar sugar sugar sugar sugar sugar sugar
Sugars
Most names for sugar end in -ose
 Classified by number of carbons

 6C = hexose (glucose)
 5C = pentose (ribose)
 3C = triose (glyceraldehyde)
H
H
HO
O
H
OH
H
H
OH
Glucose
C
CH2OH
CH2OH
O
H
OH
HO
O
H
H
HO
OH
H
Ribose
H
H
C
OH
H
C
OH
H
Glyceraldehyde
Functional groups determine function
carbonyl
aldehyde
carbonyl
ketone
Sugar structure
5C & 6C sugars form rings in solution
Carbons are numbered
Numbered carbons
C 6'
5' C
O
4' C
C1'
energy stored in C-C bonds
C3'
C2'
Simple & complex sugars

Monosaccharides
 simple 1 monomer sugars
 glucose

Disaccharides
 2 monomers
 sucrose

Polysaccharides
 large polymers
 starch
CH2OH
H
O
H
OH
H
H
OH
HO
Glucose
H
OH
Building sugars

Dehydration synthesis
monosaccharides
|
glucose
H2O
|
glucose
disaccharide
|
maltose
glycosidic linkage
Building sugars

Dehydration synthesis
monosaccharides
|
glucose
H2O
|
fructose
disaccharide
|
sucrose
(table sugar)
Polysaccharides

Polymers of sugars
 costs little energy to build
 easily reversible = release energy

Function:
 energy storage
starch (plants)
 glycogen (animals)


in liver & muscles
 structure
cellulose (plants)
 chitin (arthropods & fungi)

Linear vs. branched polysaccharides
slow release
starch
(plant)
energy
storage
glycogen
(animal)
fast release
Polysaccharide diversity
 Molecular structure determines function
in starch
in cellulose
 isomers of glucose
 structure determines function…
Digesting starch vs. cellulose
starch
easy to
digest
enzyme
cellulose
hard to
digest
enzyme
Cellulose

Most abundant organic compound on Earth
 herbivores have evolved a mechanism to digest
cellulose
 most carnivores have not
that’s why they eat meat to
get their energy &
nutrients
 cellulose = undigestible
roughage

Cow
can digest cellulose well;
no need to eat other sugars
Gorilla
can’t digest cellulose well;
must add another sugar
source, like fruit to diet
Helpful bacteria

How can herbivores digest cellulose so well?
 BACTERIA live in their digestive systems & help digest celluloserich (grass) meals
Caprophage
Ruminants
Lipids
Concentrated Energy Molecules
Lipid
 Examples





Fats
Oils
Waxes
Hormones
Sex hormones
 Testosterone (male)
 Estrogen (female)
Lipid
 Types
 Triglyceride (Fats)
 Steroids
 Phospholipids
Lipid
 Functions:
 Energy storage
 Very concentrated
 Twice the energy as carbohydrates!
 Cell membrane structure
 Protection/ Cushion organs
 Insulate body
 Think whale blubber!
Structure of Fat
Not a chain (polymer) = just a “big fat molecule”
General Structure
 Many carbon and hydrogen atoms with very few oxygen
atoms
 Hydrophobic
 Components of a triglyceride (FAT)
 3 Fatty acids + 1 Glycerol = Fat Molecule
Glycerol molecule
Fatty Acids
Saturated Fats
 Most animal fats




Solid at room temperature
Limit the amount in your diet
Contributes to heart disease
Deposits in arteries
Unsaturated Fats
 Plants, vegetables, and fish fats



Liquid at room temperature
Fat molecules don’t stack tightly together
Better choice in your diet
Other lipids in biology
 Cholesterol
 Good molecule in cell membranes
 Make hormones from it
 Including sex hormones
 But too much cholesterol in blood may lead to heart
disease
Isomers (cis and trans)
Isomers (cis and trans)
trans oleic fatty acid
increase amount low
density lipoproteins (LDL’s); add
to blood vessel placque
(artherosclerosis)
cis oleic fatty acid
canola or olive oil
Other lipids in biology
 Cell membranes are made out of lipids


Phospholipids
Heads are on the outside touching water


Tails are on the inside away from water


“like” water
“scared” of water
Forms a barrier between the cell and the outside
Proteins
Multipurpose Molecules
Proteins
 Examples
 Muscle
 Skin, hair, fingernails, claws
 Collagen, keratin
 Pepsin
 Digestive enzyme in stomach
 Insulin
 Hormone that controls blood sugar levels
Proteins
 Functions:
 Many, many functions
 Hormones
 Signals from one body system to another
 Insulin
 Movement
 Muscle
 Immune system
 Protect against germs
 Enzymes
 Help chemical reactions
Proteins
 Building block = amino acids
 20 different amino acids
Amino acid
Amino acid
Amino acid
Amino acid
Amino acid
There’s 20 of us… like 20
different letters in an
alphabet! Can make lots of
different words
Amino Acid Chain
 Proteins
Amino acids chained into a polymer
 Each amino acid is different



Some “like” water & dissolve in it…hydrophilic
Some “fear” water & separate from it…
hydrophobic
Water-fearing amino acids
 Hydrophobic
 “water fearing” amino acids
 Try to get away from water in cell
 The protein folds
Water-loving amino acids
 Hydrophilic
 “Water-loving” amino acids
 Try to stay in water in cell
 The protein folds
For Proteins: SHAPE Matters!
 Proteins fold & twist into 3-D shape
 That is what happens in the cell
 Different shapes = different jobs
It’s SHAPE that matters!

Proteins do their jobs, because of their shape

Unfolding a protein destroys its shape


Wrong shape = can’t do its job
Unfolding proteins = “denature”


Temperature
pH (acidity)