PCB 3023C Cell Biology Exam 1 Questions & Answers | Grade A
| 100% Correct - Florida Gulf Coast University
1. Which component of the cell theory was proposed by Rudolf Virchow?
A. Cells can arise only by division from a preexisting cell.
B. The cell is the structural unit of life.
C. All organisms are composed of one or more cells.
D. Cells contain genetic material passed to offspring.
Answer: A
Explanation: Virchow’s contribution to the cell theory was the tenet that all cells come from
pre-existing cells.
2. Which of the following is a characteristic shared by both prokaryotic and
eukaryotic cells?
A. Presence of a membrane-bound nucleus
B. Complex membrane-bound organelles
C. Linear DNA organized into chromosomes
D. Use of ribosomes for protein synthesis
Answer: D
Explanation: Both cell types require ribosomes to translate genetic information into
proteins, though the size of the ribosomes differs.
,3. What type of bond involves the unequal sharing of electrons between
atoms?
A. Nonpolar covalent bond
B. Ionic bond
C. Polar covalent bond
D. Hydrogen bond
Answer: C
Explanation: In polar covalent bonds, electrons are shared unequally due to differences in
electronegativity between the atoms.
4. Which molecule is primarily responsible for the fluidity of the plasma
membrane in animal cells?
A. Phospholipids
B. Glycoproteins
C. Peripheral proteins
D. Cholesterol
Answer: D
Explanation: Cholesterol acts as a fluidity buffer, preventing the membrane from becoming
too rigid in cold temperatures or too fluid in high temperatures.
5. The primary structure of a protein is held together by which type of bond?
A. Peptide bonds
B. Hydrogen bonds
C. Disulfide bridges
D. Ionic interactions
Answer: A
Explanation: The primary structure is the linear sequence of amino acids linked by covalent
peptide bonds.
, 6. Which organelle is responsible for the synthesis of lipids and the
detoxification of drugs?
A. Rough Endoplasmic Reticulum
B. Lysosome
C. Golgi Apparatus
D. Smooth Endoplasmic Reticulum
Answer: D
Explanation: The Smooth ER lacks ribosomes and is the site for lipid synthesis,
carbohydrate metabolism, and detoxification.
7. According to the endosymbiotic theory, which organelle originated from
an ancient engulfed prokaryote?
A. Mitochondrion
B. Nucleus
C. Lysosome
D. Vacuoles
Answer: A
Explanation: Mitochondria and chloroplasts have their own DNA and double membranes,
suggesting they were once free-living bacteria.
8. Which amino acid is capable of forming disulfide bonds to stabilize
protein tertiary structure?
A. Cysteine
B. Proline
C. Glycine
D. Methionine
Answer: A
Explanation: Cysteine contains a sulfhydryl (-SH) group that can form a covalent disulfide
bridge with another cysteine.
| 100% Correct - Florida Gulf Coast University
1. Which component of the cell theory was proposed by Rudolf Virchow?
A. Cells can arise only by division from a preexisting cell.
B. The cell is the structural unit of life.
C. All organisms are composed of one or more cells.
D. Cells contain genetic material passed to offspring.
Answer: A
Explanation: Virchow’s contribution to the cell theory was the tenet that all cells come from
pre-existing cells.
2. Which of the following is a characteristic shared by both prokaryotic and
eukaryotic cells?
A. Presence of a membrane-bound nucleus
B. Complex membrane-bound organelles
C. Linear DNA organized into chromosomes
D. Use of ribosomes for protein synthesis
Answer: D
Explanation: Both cell types require ribosomes to translate genetic information into
proteins, though the size of the ribosomes differs.
,3. What type of bond involves the unequal sharing of electrons between
atoms?
A. Nonpolar covalent bond
B. Ionic bond
C. Polar covalent bond
D. Hydrogen bond
Answer: C
Explanation: In polar covalent bonds, electrons are shared unequally due to differences in
electronegativity between the atoms.
4. Which molecule is primarily responsible for the fluidity of the plasma
membrane in animal cells?
A. Phospholipids
B. Glycoproteins
C. Peripheral proteins
D. Cholesterol
Answer: D
Explanation: Cholesterol acts as a fluidity buffer, preventing the membrane from becoming
too rigid in cold temperatures or too fluid in high temperatures.
5. The primary structure of a protein is held together by which type of bond?
A. Peptide bonds
B. Hydrogen bonds
C. Disulfide bridges
D. Ionic interactions
Answer: A
Explanation: The primary structure is the linear sequence of amino acids linked by covalent
peptide bonds.
, 6. Which organelle is responsible for the synthesis of lipids and the
detoxification of drugs?
A. Rough Endoplasmic Reticulum
B. Lysosome
C. Golgi Apparatus
D. Smooth Endoplasmic Reticulum
Answer: D
Explanation: The Smooth ER lacks ribosomes and is the site for lipid synthesis,
carbohydrate metabolism, and detoxification.
7. According to the endosymbiotic theory, which organelle originated from
an ancient engulfed prokaryote?
A. Mitochondrion
B. Nucleus
C. Lysosome
D. Vacuoles
Answer: A
Explanation: Mitochondria and chloroplasts have their own DNA and double membranes,
suggesting they were once free-living bacteria.
8. Which amino acid is capable of forming disulfide bonds to stabilize
protein tertiary structure?
A. Cysteine
B. Proline
C. Glycine
D. Methionine
Answer: A
Explanation: Cysteine contains a sulfhydryl (-SH) group that can form a covalent disulfide
bridge with another cysteine.
