Biochemistry Exam 1 (Multiple Choice +
Formulas) QUESTIONS AND ANSWERS
2025.
Approximately what percentage of the human genome encodes for protein? - ANSWER:
3%
What pairs of atoms in bases are involved in hydrogen bonds?
A) N-H and O-H
B) N-H and S-H
C) O-H and P-O
D) All of the above
E) None of the above - ANSWER: A) N-H and O-H
The structure of DNA described by Watson and Crick included
A) a double helix
B) the sugar phosphate backbone aligned in the center of the helix
C) the base pairs that are stacked on the inside of the double helix
D) A and B
E) A and C - ANSWER: E) A and C
What two properties of water are important for biological interactions? - ANSWER: The
polarity of water
The cohesive properties of water
How many hydrogen bonds are formed between A and T? - ANSWER: 2
What gives proteins a dominant role in biochemistry? - ANSWER: Their ability to
spontaneously fold into complex three-dimensional structures
Which of the following is considered a noncovalent bond?
A) Electrostatic interactions
, B) Hydrogen bonds
C) Van der Waals interactions
D) All of the above
E) None of the above - ANSWER: D) All of the above
The First Law of Thermodynamics states what? - ANSWER: The total energy of a
system and its surroundings is constant
The Second Law of Thermodynamics states what? - ANSWER: The total entropy of a
system and its surroundings always increases for a spontaneous process
List atoms commonly found in biological molecules that are often hydrogen-bond
acceptors. - ANSWER: Oxygen
Nitrogen
What is the [A-]/[HA] ratio when the weak acid is in a solution one pH unit below its
pKa? - ANSWER: 1:10
If a particular reaction has a negative delta-G (Gibbs Free Energy), is it likely to occur? -
ANSWER: Yes, it is spontaneous
What is the [H+] concentration in a urine sample that has a pH of 8? - ANSWER: 10^-8
M
What happens to nonpolar molecules in water? - ANSWER: They aggregate together
What type of chiral amino acids is found in proteins? - ANSWER: L
What is another name for dipolar molecules? - ANSWER: Zwitterions
When a peptide bond is formed, what molecule is also made? - ANSWER: Water
Write the name, three letter code, and single letter code for the amino acid for the
following:
A) the amino acid with a pKa near neutral pH
B) disulfide bonds are formed by pairs of which amino acid
C) this amino acid residue disrupts the alpha-helix because its side chain contains a
unique ring structure that restricts bond rotation - ANSWER: A) Histidine, His, H
B) Cysteine, Cys, C
C) Proline, Pro, P
Formulas) QUESTIONS AND ANSWERS
2025.
Approximately what percentage of the human genome encodes for protein? - ANSWER:
3%
What pairs of atoms in bases are involved in hydrogen bonds?
A) N-H and O-H
B) N-H and S-H
C) O-H and P-O
D) All of the above
E) None of the above - ANSWER: A) N-H and O-H
The structure of DNA described by Watson and Crick included
A) a double helix
B) the sugar phosphate backbone aligned in the center of the helix
C) the base pairs that are stacked on the inside of the double helix
D) A and B
E) A and C - ANSWER: E) A and C
What two properties of water are important for biological interactions? - ANSWER: The
polarity of water
The cohesive properties of water
How many hydrogen bonds are formed between A and T? - ANSWER: 2
What gives proteins a dominant role in biochemistry? - ANSWER: Their ability to
spontaneously fold into complex three-dimensional structures
Which of the following is considered a noncovalent bond?
A) Electrostatic interactions
, B) Hydrogen bonds
C) Van der Waals interactions
D) All of the above
E) None of the above - ANSWER: D) All of the above
The First Law of Thermodynamics states what? - ANSWER: The total energy of a
system and its surroundings is constant
The Second Law of Thermodynamics states what? - ANSWER: The total entropy of a
system and its surroundings always increases for a spontaneous process
List atoms commonly found in biological molecules that are often hydrogen-bond
acceptors. - ANSWER: Oxygen
Nitrogen
What is the [A-]/[HA] ratio when the weak acid is in a solution one pH unit below its
pKa? - ANSWER: 1:10
If a particular reaction has a negative delta-G (Gibbs Free Energy), is it likely to occur? -
ANSWER: Yes, it is spontaneous
What is the [H+] concentration in a urine sample that has a pH of 8? - ANSWER: 10^-8
M
What happens to nonpolar molecules in water? - ANSWER: They aggregate together
What type of chiral amino acids is found in proteins? - ANSWER: L
What is another name for dipolar molecules? - ANSWER: Zwitterions
When a peptide bond is formed, what molecule is also made? - ANSWER: Water
Write the name, three letter code, and single letter code for the amino acid for the
following:
A) the amino acid with a pKa near neutral pH
B) disulfide bonds are formed by pairs of which amino acid
C) this amino acid residue disrupts the alpha-helix because its side chain contains a
unique ring structure that restricts bond rotation - ANSWER: A) Histidine, His, H
B) Cysteine, Cys, C
C) Proline, Pro, P
