BIOD 101 COMPREHENSIVE EXAM
(MODULES 1-6) QUESTIONS &
VERIFIED ANSWERS (A+ GUARANTEE)
1. If the pH of a solution is decreased from 7 to 5, how has the concentration of hydrogen ions
[H+] changed?
A. It has increased by 2 times
B. It has decreased by 100 times
C. It has increased by 100 times
D. It has decreased by 2 times
Answer: C
Conceptual Explanation: The pH scale is logarithmic. Each unit change represents a
tenfold change in H+ concentration. Moving from 7 to 5 is a change of 2 units (10 x 10 =
100), and a lower pH indicates a higher concentration of H+.
2. Which of the following organic molecules contains a glycosidic linkage between two
monosaccharides?
A. Triglyceride
B. RNA
C. Hemoglobin
,D. Lactose
Answer: D
Conceptual Explanation: Lactose is a disaccharide formed by a glycosidic linkage between
glucose and galactose. Triglycerides have ester linkages, proteins have peptide bonds, and
nucleic acids have phosphodiester bonds.
3. What type of protein structure is characterized by the specific three-dimensional folding of
a single polypeptide chain due to side-chain (R-group) interactions?
A. Primary
B. Secondary
C. Quaternary
D. Tertiary
Answer: D
Conceptual Explanation: Tertiary structure refers to the overall 3D shape of a single
polypeptide, stabilized by hydrophobic interactions, disulfide bridges, ionic bonds, and
hydrogen bonds between R-groups.
4. During DNA replication, which enzyme is responsible for unwinding the double helix at the
replication fork?
A. DNA Polymerase III
B. Ligase
, C. Primase
D. Helicase
Answer: D
Conceptual Explanation: Helicase breaks the hydrogen bonds between the nitrogenous
bases to separate the strands. Primase adds RNA primers, Polymerase builds the new
strand, and Ligase joins fragments.
5. In a hypertonic solution, what will happen to a typical animal cell?
A. It will shrivel (crenate)
B. It will undergo plasmolysis
C. It will swell and potentially lyse (burst)
D. It will remain in dynamic equilibrium
Answer: A
Conceptual Explanation: A hypertonic solution has a higher solute concentration than the
cell’s cytoplasm. Water will move out of the cell by osmosis, causing the cell to shrivel.
6. Which organelle is responsible for the detoxification of drugs and the storage of calcium
ions in muscle cells?
A. Rough Endoplasmic Reticulum
B. Smooth Endoplasmic Reticulum
C. Lysosome
(MODULES 1-6) QUESTIONS &
VERIFIED ANSWERS (A+ GUARANTEE)
1. If the pH of a solution is decreased from 7 to 5, how has the concentration of hydrogen ions
[H+] changed?
A. It has increased by 2 times
B. It has decreased by 100 times
C. It has increased by 100 times
D. It has decreased by 2 times
Answer: C
Conceptual Explanation: The pH scale is logarithmic. Each unit change represents a
tenfold change in H+ concentration. Moving from 7 to 5 is a change of 2 units (10 x 10 =
100), and a lower pH indicates a higher concentration of H+.
2. Which of the following organic molecules contains a glycosidic linkage between two
monosaccharides?
A. Triglyceride
B. RNA
C. Hemoglobin
,D. Lactose
Answer: D
Conceptual Explanation: Lactose is a disaccharide formed by a glycosidic linkage between
glucose and galactose. Triglycerides have ester linkages, proteins have peptide bonds, and
nucleic acids have phosphodiester bonds.
3. What type of protein structure is characterized by the specific three-dimensional folding of
a single polypeptide chain due to side-chain (R-group) interactions?
A. Primary
B. Secondary
C. Quaternary
D. Tertiary
Answer: D
Conceptual Explanation: Tertiary structure refers to the overall 3D shape of a single
polypeptide, stabilized by hydrophobic interactions, disulfide bridges, ionic bonds, and
hydrogen bonds between R-groups.
4. During DNA replication, which enzyme is responsible for unwinding the double helix at the
replication fork?
A. DNA Polymerase III
B. Ligase
, C. Primase
D. Helicase
Answer: D
Conceptual Explanation: Helicase breaks the hydrogen bonds between the nitrogenous
bases to separate the strands. Primase adds RNA primers, Polymerase builds the new
strand, and Ligase joins fragments.
5. In a hypertonic solution, what will happen to a typical animal cell?
A. It will shrivel (crenate)
B. It will undergo plasmolysis
C. It will swell and potentially lyse (burst)
D. It will remain in dynamic equilibrium
Answer: A
Conceptual Explanation: A hypertonic solution has a higher solute concentration than the
cell’s cytoplasm. Water will move out of the cell by osmosis, causing the cell to shrivel.
6. Which organelle is responsible for the detoxification of drugs and the storage of calcium
ions in muscle cells?
A. Rough Endoplasmic Reticulum
B. Smooth Endoplasmic Reticulum
C. Lysosome
