Download Protein practice MULTIPLE CHOICE. Choose the one

Protein practice
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) Which of the following amino acids contains sulfur in the side chain?
A) Phenylalanine
B) Cysteine
C) Tyrosine
D) Glycine
1)
2) Which of the following amino acids is classified as being hydrophobic?
A) Histidine
B) Cysteine
C) Arginine
D) Phenylalanine
2)
3) Corn is an incomplete protein because it lacks one or more:
A) amino acids
B) amino acids containing sulfur
C) free amino acids
D) essential amino acids
3)
4) The interaction of the side chains on the amino acids, for example hydrophobic attractions, is the
________ structure of a protein.
A) primary
B) secondary
C) tertiary
D) quaternary
4)
5) Which type of forces stabilizes the primary structure of a protein?
A) Peptide bonds
B) Hydrogen bonding between the carbonyl group and amino group
C) Salt bridges
D) Dipole-dipole
5)
6) Which type of forces stabilizes the secondary structure of a protein?
A) Peptide bonds
B) Hydrogen bonding between the carbonyl group and amino group
C) Salt bridges
D) Dipole-dipole
6)
7) Which pair of amino acids can have nonpolar (hydrophobic) interactions?
A) Arginine and glutamate
B) Phenylalanine and valine
C) Cysteine and cysteine
D) Tyrosine and serine
7)
8) The alpha-helix is an example of:
A) primary structure
C) tertiary structure
8)
B) secondary structure
D) quaternary structure
9) Which of the following is an example of globular protein?
A) Keratins
B) Collagen
C) Myoglobin
9)
D) Skin
10) What type of stabilizing interaction would be expected between phenylalanine and valine?
A) Salt bridges
B) Hydrogen bonds
C) Disulfide bonds
D) Hydrophobic interaction
10)
11) Which of the following is an example of a fibrous protein?
A) Collagen
B) Myoglobin
C) Hemoglobin
11)
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D) Albumin
12) A protein that is comprised of two or more protein chains that interact to make the overall
structure is called the:
A) primary structure
B) secondary structure
C) tertiary structure
D) quaternary structure
12)
13) Heavy metals such as Pb+2 or Hg +2 denature proteins by reacting with:
A) the proline residues
B) the OH group of tyrosine residues
13)
C) the SH group of cysteine residues
D) the NH2 group of glutamine
14) Detergents would most likely disrupt what type of stabilizing interaction?
A) Salt bridges
B) Hydrogen bonds
C) Disulfide bonds
D) Hydrophobic interaction
14)
15) Which of the following is an example of a transport protein?
A) Hemoglobin
B) Collagen
C) Pepsin
15)
D) Oxytocin
16) Which of the following proteins has a distinctive Y-shape?
A) Hemoglobin
B) Collagen
C) Antibodies
D) Integral protein
16)
17) The area on the enzyme that interacts with the substrate is called the:
A) regulatory site
B) modulator site
C) active site
D) allosteric site
17)
18) Molecular collisions in a reaction are necessary for a reaction to take place because:
A) the reactant molecules must directly interact with each other to produce product
B) the collisions of rapidly moving molecules provide energy
C) the number of collisions
D) all of the above
18)
19) The minimum energy that reactants need in order for the molecules to be in the correct
orientation is called:
A) collision energy
B) dissociation energy
C) activation energy
D) orientation energy
19)
20) A fast reaction rate for a chemical reaction is dependent on:
A) having a large activation energy
B) having a small activation energy
C) being exothermic
D) being endothermic
20)
21) What is the primary function of enzymes?
A) Neurotransmitters
C) Structure
21)
B) Biochemical catalysts
D) Transport
22) What factors can influence the speed of a reaction by an enzyme?
A) The orientation of the reactants
B) The weakening of bond energies in the reactants
C) The closeness of the reactants to each other in the active site
D) All of the above
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22)
23) Enzymes function as a catalyst by:
A) changing the energetic involved in a reaction
B) changing the equilibrium constant
C) increasing the time it takes for a reaction to take place
D) lowering the activation energy of a reaction
23)
24) An enzyme will increase the rate of certain reactions with certain substances. This characteristic
is called:
A) selectivity
B) specificity
C) regulation
D) inhibition
24)
25) The pH of the environment in which an enzyme is located can influence the reactivity because a
change in pH:
A) can hydrolyze the protein
B) can produce protonation or deprotonation of residues in the active site
C) changes the primary structure
D) affects the optical activity
25)
26) The process of competitive inhibition can be overcome by:
A) increasing the pH
B) increasing the substrate concentration
C) decreasing the temperature
D) all of the above
26)
27) The optimum pH for an enzyme such as pepsin that works to break down peptide bonds would
be:
A) acidic
B) basic
C) neutral
D) all of the above
27)
28) The optimum pH for an enzyme such as hexokinase that phosphorylates glucose in the blood
would be:
A) 2.0
B) 7.4
C) 9.0
D) none of these
28)
29) A reversible inhibitor is one that:
A) binds permanently to the enzyme
C) denatures the enzyme
29)
B) binds temporarily to the enzyme
D) activates the enzyme
30) The function of myoglobin is
A) stores oxygen in myocytes
C) transport s oxygen
B) reacts with oxygen to make water
D) produces ATP in myocyte
30)
31) Jello is made from animal connective tissues (collagen). The most prevalent amino acids in
collagen are
A) G and F
B) E and D
C) C and N
D) G and P
31)
32) Keratin is a protective protein present in hair, skin, nails and horns. Why are nails harder than
hair?
A) There is more gly in hair
B) There are more disulfide linkages in nails
C) There is more lys in nails
D) There is more pro in nails
32)
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Answer Key
Testname: PROTEINPRACTICE
1) B
2) D
3) D
4) C
5) A
6) B
7) B
8) B
9) C
10) D
11) A
12) D
13) C
14) D
15) A
16) C
17) C
18) D
19) C
20) B
21) B
22) D
23) D
24) B
25) B
26) B
27) A
28) B
29) B
30) A
31) D
32) B
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