Bio102 Problems
Fluid Mosaic Model
1. A peptide bond is formed by a(n) ___________.
A. dehydration reaction
B. equilibrium reaction
C. hydrogen bond
D. hydrolysis reaction
E. disulfide bond
2. Which one of the following is an example of a secondary structure?
A. Beta Sheet
B. Triglyceride
C. Double Helix
D. Disulfide Bridge
E. Peptide Bond
3. Which one statement accurately describes condensation reactions?
A. Condensation reactions are used to break down polymers into monomers.
B. Water is consumed during condensation reactions.
C. A condensation reaction is the same thing as a hydrolysis reaction.
D. Condensation reactions can be used to connect amino acids with peptide bonds.
E. Condensation reactions are used to connect phospholipids together to make a cell membrane less
permeable.
4. Which one force does NOT contribute to the tertiary structure of a protein?
A. Hydrogen bonding
B. Micelle interactions
C. van der Waals interactions
D. Disulfide bridges
E. Ionic interactions
5. Which one of the following forces does NOT contribute to tertiary structure?
A. Hydrogen bonds
B. Amphipathic bonds
C. Disulfide bonds
D. Van der Waals (hydrophobic) interactions
E. Ionic bonds
6. Which one of the following does NOT contribute to the secondary structure of a protein?
A. Hydrogen bonding
B. Activation energy interactions
C. Hydrophobic interactions
D. Ionic bonding
E. Disulfide bridges
7. Not all proteins have quaternary structure. This is because not all proteins
A. contain peptide bonds.
B. have quaternary amines.
C. contain at least one disulfide bridge.
D. contain the amino acid quaternine.
E. bind another protein.
8. The fluid mosaic model of membrane structure predicts that the plasma membrane
A. prevents the destruction of the cell by osmosis.
B. is more fluid than the cell membrane.
C. restricts the lateral movement of phospholipids.
D. forms a rigid structure to prevent the loss of important molecules.
E. contains proteins.
9. Which of the following might have a secondary structure?
A. Phospholipid
B. Cholesterol
C. Amino Acid
D. Tyrosinase
E. Peptide Bond
10. If a protein is amphipathic it is likely
A. to be made of many amino acids.
B. found in a membrane.
C. to have quaternary structure.
D. to be an enzyme.
E. to be at or near it’s Vmax value.
11. Protein fill-in-the-blank:
A. The “back” end of a protein is better called the ___Carboxy terminus_______.
B. Individual units are held together by this special type of covalent bond: __Peptide bond__.
C. A protein is a polymer of many __amino acids__________.
D. An -helix is one type of ___secondary structure_.
12A. Show the chemical structures of the three groups attached to the central carbon of an amino acid.
H
H
H-N-
O
C
-C-OH
Side
Group
12B. The ‘front’ end of a protein is better known as the _ Amino- (or N-) terminus __.
12C. An -helix (alpha-helix) is an example of a type of __Secondary_________ structure.
13. Peptide bonds are found in
A. phospholipids.
B. cholesterol.
C. proteins.
D. DNA.
E. pyrocatechol.
14. Proteins can be polymerized
A. on the rough endoplasmic reticulum (ER).
B. within the vacuole.
C. in the nucleolus.
D. by a hydrolysis reaction.
E. as they move through the nuclear pore.
15. Which of the following molecules is an amino acid? Circle all that apply.
16. The structures of five amino acids are shown below.
16A. Which amino acid is most likely to be found in a transmembrane domain? Why?
Valine. It’s the only one with a hydrophobic side chain.
16B. Draw the structure of a Serine-Valine-Glutamate tripeptide and name both ends.
N- (amino) terminus
O
O
O
||
||
||
H2N – CH – C – NH – CH – C – NH – CH – C - OH
|
|
|
CH2OH
CH-CH3
CH2-CH2-COOH
|
CH3
C- (carboxyl) terminus
16C. Name one example of a secondary structure. _____-helix__________
Glutamate
Glutamine
Lysine
Serine
Valine
17A. What are the four different groups that are covalently linked to the central carbon of an amino
acid?
____carboxylic acid___________
_____hydrogen_______________
_____amino group_____________
_____variable side group________
17B. The ‘back’ end of a protein is more properly known as the __carboxyl (or C-) terminus_.
17C. An -helix (alpha-helix) is an example of a type of _____secondary______ structure.
17D. Circle the one structure below that is a peptide bond. (1 point)
H H
| |
-N – N-
O
O
||
||
-C – O – C-
O
H
O
H
O O
||
|
||
|
|| ||
-C – O – N-
-C – N-
-C – C-
17E. On what cellular structure are peptide bonds synthesized? _______Ribosomes_______
18. Which one of the following is an example of a secondary structure?
A. triglyceride
B.  -sheet
C. co-enzyme
D. transmembrane domain
E. rhodopsin
19A. The side chains and abbreviations of three amino acids are shown below. Draw the structure of
the Ser-Lys-Ala tripeptide and label both ends.
Serine
-CH2-OH
(Ser)
Lysine
-CH2-CH2-CH2-CH2-NH3+
(Lys)
H O H H O H H O
│
║
│
│
║
│
│
║
H2N – C – C – N – C – C – N – C – C – OH
│
│
│
CH2-OH (CH2)4-NH3+ CH3
N-terminus
C-terminus
Alanine
-CH3
(Ala)
19B. These peptide bonds can be synthesized on what two eukaryotic structures?
_____Free Ribosomes____ and __Rough Endoplasmic Reticulum__
20. What kind of a covalent bond can contribute to the quaternary structure of an enzyme?
_____Disulfide______