C190 MODULE 2 - CELLS | CELL STRUCTURES AND TYPES | CELL
STRUCTURES AND TYPES | MULTICHOICE ANSWERED EXAM
QUESTIONS WITH DETAILED RATIONALES
1. What is the basic unit of life?
A. Tissue
B. Organ
C. Cell ✅
D. Organ system
Rationale: Cells are the smallest structure capable of independent life and carry out all
life processes.
2. Which organelle is responsible for generating energy in a cell?
A. Nucleus
B. Golgi apparatus
C. Mitochondria ✅
D. Endoplasmic reticulum
Rationale: Mitochondria perform oxidative phosphorylation to produce ATP — the cell’s
main energy currency.
3. What are the stages of the cell cycle in order (major phases)?
A. Interphase, Prophase, Metaphase, Anaphase, Telophase
B. G1 phase, S phase, G2 phase, Mitosis ✅
C. Cytokinesis, Interphase, G1 phase, S phase
D. G2 phase, Prophase, Telophase, Cytokinesis
Rationale: Interphase comprises G1 → S → G2; Mitosis (M) follows (prophase →
metaphase → anaphase → telophase), then cytokinesis.
4. During which phase of the cell cycle does DNA replication occur?
A. G1 phase
B. G2 phase
C. S phase ✅
D. Metaphase
Rationale: S (synthesis) phase is when the entire genome is duplicated prior to mitosis.
5. What is the primary purpose of cell signaling?
A. To ensure cell division occurs
B. To regulate gene expression
C. To facilitate communication between cells ✅
D. To initiate cellular adaptations
, ESTUDYR
Rationale: Cell signaling enables cells to receive/process external information and
coordinate responses (including gene regulation, division, adaptation).
6. Which class of molecules is most commonly involved as ligands or receptors in cell
signaling?
A. Proteins ✅
B. Nucleic acids
C. Lipids
D. Carbohydrates
Rationale: Proteins (e.g., hormones, cytokines, receptors) are predominant signaling
molecules due to structural diversity and specificity.
7. What is cell differentiation?
A. The process of cell division
B. The specialization of cells to perform specific functions ✅
C. The regulation of gene expression
D. The formation of new cells
Rationale: Differentiation is the process where pluripotent/precursor cells adopt
specialized structure and function through altered gene expression.
8. Which of the following best describes a specialized cell?
A. Able to perform multiple functions
B. Capable of dividing rapidly
C. Adapted to carry out specific tasks ✅
D. Undifferentiated and unspecialized
Rationale: Specialized cells have structure and gene expression suited to narrow
functions (e.g., neurons, erythrocytes).
9. Which process allows cells to adapt to changes in their environment?
A. Cell division
B. Cell differentiation
C. Cell signaling
D. Cellular adaptations ✅
Rationale: Cellular adaptations (hypertrophy, hyperplasia, atrophy, metaplasia) are
structural/functional changes in response to stress.
10. Examples of cellular adaptations include:
A. Changes in cell size and shape
B. Development of resistance to toxins
C. Alterations in metabolic activity
D. All of the above ✅
Rationale: Adaptations cover morphological and biochemical changes enabling cells to
survive altered conditions.