Proteins
What are the building blocks of proteins and what are the 5 parts of its structure?
Building blocks: amino acids
1. Amino group (NH3)
2. R group
3. Central/alpha carbon
4. Hydrogen
5. Carboxyl group (COO-)
What are the building blocks of nucleic acids? Describe its structure.
Building blocks: nucleotides
1. Phosphate group
2. 5 carbon sugar
3. Nitrogenous base
What is the monomer for carbohydrates, and what is the chemical formula of the most common monomer?
Monomer: monosaccarides
Most common monosaccharide: Glucose (C6H12O6)
What are the two main functions of lipids?
1. Energy storage
2. Membrane structure
What are the valence values for hydrogen, oxygen, nitrogen, and carbon?
Hydrogen: 1
Oxygen: 2
Nitrogen: 3
Carbon: 4
How do proteins have directionality?
Proteins have directionality due to the N and C terminus.
N terminus: amino group and the end
C terminus: carboxyl group at the end
What is the difference between DNA and RNA?
DNA:
- Uses A, T, C, and G nucleotides
- Uses deoxyribose as its 5 C sugar
- Double stranded
RNA:
- Uses A, U, C, and G nucleotides
- Uses ribose as its 5 C sugar
- Single stranded
What is the name of the bond that holds together monosaccharides?
Glycosidic bond
How are fatty acids amphipathic?
1. Polar head w/ a carboxyl group (COO-)
2. Hydrocarbon tail
Why can water be considered a polar molecule?
Oxygen has a greater electronegativity than hydrogen, resulting in the e- hanging around oxygen more, creating a polar bond.
The oxygen is therefore more (-) while the hydrogen is more (+).
Polar: will contain polar functional groups
(OH, -SH, O)
Non-polar: will contain only hydrocarbons
Charged: will contain a + or - charge on an atom
How does DNA have directionality?
Through the 5' and 3' ends
5': Phosphate group
3': OH group
What is the difference between α-D-glucose and β-D-glucose?
α-D-glucose: the OH group is under the ring at 1'C
β-D-glucose: the OH group is above the ring at 1'C
What is the difference between saturated and unsaturated fatty acids?
Saturated: consists of only single bonds, resulting in a linear chain, thus having a higher melting point
Unsaturated: consists of at least one double bond, resulting in a kink in the chain, thus having a lower melting point
Double Jeopardy!
What are the 7 functional groups?
1. Carboxyl (COOH or COO-)
2. Hydroxyl (OH-)
3. Sulfhydrl (SH-)
4. Amino (NH3+)
5. Aldehyde (C=O-H)
6. Carbonyl (C=O)
7. Phosphate (PO4-)
What are the four levels of protein structure? Describe each one.
1. Primary: linear chain of amino acids
2. Secondary: alpha helices and beta pleated sheets form between amino acids
3. Tertiary: 3D folding of polypeptide
4. Quaternary: Multiple polypeptide subunits coming together
What bonds can be found in DNA? How is DNA anti-parallel?
1. Phosphodiester bond: holds together nucleotides on the OH group found on the 3' C and the phosphate group of another nucleotide
2. Hydrogen bond: holds together the nitrogenous bases
DNA is anti-parallel since one strand goes from 5' -> 3', while another goes 3' -> 5'
Which of the 3 common polysaccharides cannot be broken down by humans and why?
Cellulose - humans can't break it down since we don't have the enzyme responsible for breaking it down and it's too rigid
Describe the 2 types of phospholipids and the structure of the most common type.
Phosphoglyceries (most common) and sphingolipids
1. Phosphate group
2. R group
3. Glycerol group
4. 2 fatty acids
What can go through the phospholipid bilayer? What can't?
Can go through with ease:
- Small, non-polar molecules
- Small, uncharged molecules
Cannot go through, requires more help:
- Ions
- Large, polar molecules
Double Jeopardy!
List all of the bonds present in each level of protein structure.
Primary: peptide bonds
Secondary: hydrogen and peptide bonds
Tertiary: ionic, disulfide, hydrophobic interactions, hydrogen, and van der waals interactions
Quaternary: ionic, disulfide, hydrophobic interactions, hydrogen, and van der waals interactions
T/F: A DNA strand with a higher G-C content will require a lower melting/denaturation temperature.
False, since there are 3 hydrogen bonds between G and C, more energy is required to break all of those bonds
Double Jeopardy!
What are some common polysaccharides, what is their function, and in which cell type can they be found?
1. Glycogen: for energy storage, can be found in animal cells (liver and muscle)
2. Starch: for energy storage, can be found in plant cells
3. Cellulose: for structure, can be found in plant cell walls
What are the functions of cholesterol?
- Acts a precursor to steroid hormones (ex. estrogen)
- Regulates membrane fluidity
What kinds of chemical bonds/interactions can be found in macromolecules?
1. Hydrophobic interactions
2. Hydrogen bonds
3. Covalent bonds
4. Van der Waals
5. Ionic bonds