Transcript H - morescience

Macromolecules
Building Blocks
of Life
Macromolecules
 Smaller organic molecules join together
to form larger molecules

macromolecules
 4 major classes of
macromolecules:
carbohydrates
 lipids
 proteins
 nucleic acids

Macromolecule
Carbohydrate
Lipid
Protein
Nucleic Acid
Chemistry
Monomer
CHO (1:2:1) monosaccharide
None, made of
CHO (H>O)
Glycerol &
3 fatty acids
CHON
CHONP
Bonds
Other
Glycosidic
Bonds
Covalent via
dehydration syn
-ose = sugar
Ester Bonds
Double - unsat.
Single – sat
dehydration syn
-Ex. Glucose,
cellulose, glycogen
For long term
storage, insulation,
Hormones,
membrane structure
amino acid
-in -ase
Covalent Insulin, hemoglobin,
Peptide Bonds
actin, myosin,
Disulfide Bridge, Ionic
chitin, collagen
Hydrogen Bond
Catalase, lipase, lactase,
dehydration syn
protease
nucleotide
Btw N bases Hydrogen Bonds
5’ and 3’ C’s Phosphodiester
Bonds
dehydration syn
RNA, DNA
- stores genetic code,
blue print of life
Polymers
 Long molecules built by linking repeating
building blocks in a chain

monomers
 building blocks
 repeated small units

H 2O
covalent bonds
HO
H
HO
H
Dehydration synthesis
HO
H
How to build a polymer
 Synthesis

You gotta
be open to
“bonding!
joins monomers by “taking” H2O out
 one monomer donates OH–
 other monomer donates H+
 together these form H2O

H 2O
requires energy & enzymes
HO
H
Dehydration synthesis
HO
HO
H
enzyme
H
Counting carbons in glucose:
6
5
1
4
3
2
Carbohydrate Dehydration
Play: 05-05-Disaccharides.swf in internet browser
Play: 05-07-Polysaccharides.swf in internet browser
Hands-On Application
Build a polysaccharide using the three monosaccharides (glucose molecules)
To bond two glucose molecules together, you must first:
1. Cut off a H from the (hydroxyl group –OH) from Carbon 1 and
2. Cut off an –OH from Carbon 4 from the second glucose molecule.
Then glue the 2 molecules together at the Oxygen forming a glycosidic bond.
Repeat for the third glucose molecule.
Questions: How many glucose molecules were joined?
How many water molecules were formed?
Why is this called Dehydration Synthesis?
Create an equation to determined how many water molecules are formed.
Carbohydrate Rings
Complex Carbohydrates
Storage of
energy in
plants
We can digest
these a links btw
glucose molecules
Accessing glucose
for cellular
respiration
Strength in
plants
We cannot digest
these b links btw
glucose molecules
So the undigested
cellulose is fiber
that keeps our
digestive tract
moving
Complex Carbohydrates
Glycogen:
Intermediate Storage of energy in animals, analogous to starch in plants.
Highly branched (unlike starch)
Synthesized and stored mainly in the liver and muscles.
Our body uses glucose, then glycogen, then fat reserves.
Complex Carbohydrates
Cellulose:
Cellulose is found in the cell wall of plants, algae, and secreted
by some bacteria as biofilm. It forms a straight chain polymer:
unlike starch or glycogen, no coiling or branching occurs, rather
it forms a stiff rod-like crystalline configuration.
Breaking up
is hard to do!
How to break down a polymer
 Digestion

use H2O to breakdown polymers
 reverse of dehydration synthesis
 cleave off one monomer at a time
 H2O is split into H+ and OH–
 H+ & OH– attach to ends
requires enzymes
HO
 releases energy
H2O

enzyme
H
Hydrolysis
Digestion
HO
H
HO
H
Figure 5.10 The synthesis and structure of a fat, or triglyceride molecule.
Figure 5.11 Examples of saturated and unsaturated fats and fatty acids
Trans Fat is formed by adding hydrogen,
making a liquid into a solid.
Single bonds - between all carbon
atoms, saturated with Hydrogen atoms
Double bonds - between some carbon
atoms, missing some Hydrogen atoms
Hands-On Application
Building a Lipid Molecule:
Form an ester bond between the glycerol & fatty acid molecules by:
1. removing a hydrogen (H) from (-OH end) of glycerol molecule and
2. removing a hydroxyl (-OH) group from the fatty acid molecule.
a. Build one triglyceride with saturated fatty acids
b. Build a second triglyceride with polyunsaturated fatty acids
(note the difference between Saturated/Unsaturated fat.)
Questions:
How many fatty acid molecules are used to make a lipid?
How many glycerol molecules are used to make a lipid?
What is this process called? And Why?
Amino Acids (backbone + R group)
An amine group (NH3)
A carboxyl group (COOH)
R Group (amino acid side chain)
Methionine (Met) is the Start Codon for making proteins (DNA - mRNA - rRNA - tRNA - Protein)
Amino Acids (backbone + R group)
Cold sores tend to surface when people are stressed.
Stress increases the body’s acidic levels, what might be happening to Lysine?
Amino Acid Structure
Hands-On Application
Amino
Group
Carboxyl
Group
Building a Protein (Polypeptide Molecule):
1. Form an peptide bond between the carboxyl and amino groups by:
a. removing a hydroxyl (-OH) from the carboxyl end and
b. removing a hydrogen (H) from the amino end.
2. Cut off the R’s for the R-Group side chain and
3. For each R, write one for a specific amino acid, beginning with Methionine
the Start Codon.
Amino
Group
Questions:
What is the backbone of all amino acids, thus proteins?
Which amino acid begins all protein synthesis?
What is this process called? And Why?
Combine Amino Acids to make Protein
Building your protein
Cut off the hydroxyl group (OH-) from the carboxyl end (COOH)
Cut off the hydrogen ion (H+) from the amine end (NH3)
Write in a R-Group Side chain
Dehydration synthesis
Figure 5.19 A single amino acid substitution in a protein causes sickle-cell disease
A different amino acid, Valine in position 6 instead of Glutamic Acid,
Changes the protein structure and function of hemoglobin
SS = Homozygous Dominant (normal blood) - subject to malaria
Ss = Heterozygous - resistant to malaria
ss = Homozygous Recessive (sickled red blood cells)
Protein Structures & Bonds
Changing the structure changes the function
Figure 5.29 The components of nucleic acids
Glycosidic bond
Phosphodiester bonds
- Phosphate
- Sugar
- Nitrogenous Base
Chargaff Base-Pair Rule:
Adenine = Thymine
Cytosine = Guanine
Building Nucleic Acids
Phosphodiester bond
Cytosine
Glycosidic bond
H 2O
H2O
This is the 1st nucleotides
5
1
4
3
2
1. Phosphate
2. Sugar
3. Base
1. Phosphate
2. Sugar
3. Base
P
C
S
P
A
S
Scotch Tape = Hydrogen Bond
H2O
5
1
4
3
Elmers Glue = Covalent Bonds
Phosphodiester bonds
P
3’
2
C
H2O
5’
H2O
S
H2O
P
H2O
H2O
5’
A
S
3’
H2O
H2O
Glycosidic bond
String covalent bond
Figure 5.29 The components of nucleic acids