Chapter 5: Structure and Function of Large Biological Molecules Flashcards
What is dehydration?
Synthesis (making) of a polymer
How does dehydration work?
One polymer : One monomer
- Water is taken out -
OH from polymer : H from monomer
- Monomer joins Polymer to make a long polymer
What is hydrolysis?
Breaking of a polymer
How does hydrolysis work?
Water is added to a long polymer
A H from the polymer binds with the OH of the water, making a monomer and breaking off
Carbohydrates are polymers of _______.
Sugar
Carbohydrate monomers are ___________.
Monosaccharides
Two monosaccharides are called ___________________.
Disaccharides
The covalent bind between two monosaccharides is called a _________________.
Glycosidic linkage
Carbohydrate polymers are polysaccharides.
There are two types, what are they?
- Storage Polysaccharides
- for fuel
- starch for plan fuel
- glycogen for animal fuel
- Structural Polysaccharides
- for building material
- cellulose in plant cell walls
Proteins are polymers of ____________.
Amino acids
All protein monomers have an _______ group and a ________ group.
Amino, carboxyl
Is glucose soluble in water?
Yes, it is hydrophilic
The covalent bond between two amino acids is called a _______________.
Peptide bond
What are the four levels of protein structure?
Primary
Secondary
Tertiary
Quaternary
What happens in primary protein structure?
- There’s an amino acid sequence
- It could contain:
- hydrogen bond
- ionic bond
- van der waals
What happens in secondary protein structure?
- Amino acid sequence either forms:
• a helix (loop-d-loop)
• b strand (b pleated sheet)
What happens in tertiary protein structure?
The a helix or b stands fold up into a 3D shape
What happens in quaternary protein structure?
Two polypeptides come together to make a protein
How is protein structure affected in a sickel-cell hemoglobin?
- One of the amino acids in primary structure is different
- Different folding in secondary
- Different shaping in tertiary due to distorted H bonding
- Hemoglobin clumps up too closely together rather than binding to oxygen
Why are lipids not considered polymers?
Not composed of chains of repeating subunits
What is denaturation?
When the protein loses its shape
{$$} –> ~~~~
Why does denaturation happen?
Change in:
- pH
- salt concentration
- temperature
Are denatured proteins functional? Why or why not?
No.
The protein’s function depends on its structure
What is renaturation?
When the denatured protein refolds back into a normal protein
What renatures the denatured protein?
The Chaperon protein
What do nucleic acids do?
Store and transmit hereditary info
What are the two types of nucleic acids?
DNA
RNA
What do nucleotides consist of?
- Phosphate group
- 5-carbon pentose sugar
- Nitrogenous base
What are pyrimidines? Which nucleotides are pyrimidines?
Compounds that produce RNA and DNA
C T U
{__} {__} {__}
^single ring structures
(cYtosine, thYmine = pYrimidine)
What are purines? Which nucleotides are purines?
Compounds that produce DNA and RNA
A G
{}{__} {}{__}
^double ring structures
Nucleic acids are polymers of ______________.
Nucleotides
Define polynucleotide
Polymer of nucleotides
The covalent bind between two nucleotides is called a ______________.
Phosphodiester linkage
How does base pairing occur? (A to T and C to G)
Hydrogen bonding
Which base pairs are most stable? A with T or C with G? Why?
C with G
They have 3 hydrogen bonds between them, whereas A and T only have 2.
Are lipids usually polar or nonpolar? Hydrophilic or hydrophobic?
Nonpolar, hydrophobic
Fats are types of _____.
What are the two types of fat?
Lipids
Saturated and unsaturated
What are saturated fats?
- Hydrogen is bonded to carbons all the way around
H H H
| | |
H - C - C - C - H
| | |
H H H
- Has a lot of Van Der Waals to keep it closely packed like a solid
- eg butter
What are unsaturated fats?
- Less hydrogens bonded to carbons, meaning some carbons have double bonds.
H H H
| | |
H - C = C - C - H
|
H
- Has less Van Der Waals so it acts more fluid like
- eg oil
Which type of fat would you expect to be more fluid at room temperature?
A. Saturated fat
B. Monounsaturated fat
C. Polyunsaturated fat
C.
Polyunsaturated means there’s more than 1 double bond, therefore it’s more fluid.
Why is it bad to eat too many saturated fats?
They are hydrophobic so they don’t dissolve in water, meaning it can form arterial clumps and blood clots.
How are fats absorbed?
- Broken down into fatty acids by lipase
- Fatty acids diffuse through membrane and reformed
- Form into chylomicrons
- Enter lacteals and carried away by lymph
What is a phospholipid?
Phosphate head with fatty acid tails
Is the phospholipid head polar or nonpolar? Hydrophobic or hydrophilic?
Polar, hydrophilic
Is the fatty acid tail polar or nonpolar? Hydrophobic or hydrophilic?
Nonpolar, hydrophobic
Cholesterol is a _______.
Steroid
Where would you expect to find cholesterol?
Within the fatty acid tails of the cell membrane.
Cholesterol is hydrophobic, therefore it wants to be with the hydrophobic fatty acid tails.
