AND CORRECT ANSWERS WITH RATIONALE
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This extensive question bank is a dedicated study tool for the UVIC BIO 150
final exam, covering fundamental concepts from cell biology to ecology. It
systematically tests knowledge of the scientific method, atomic structure,
biological molecules, and cellular processes like mitosis and meiosis. The
questions explore plant physiology, including nutrient uptake, transport
mechanisms, and hormonal regulation. Animal tissue types, organ systems,
and evolutionary principles such as natural selection and speciation are also
rigorously examined. Each question is paired with a correct answer and a
detailed rationale, ensuring deep conceptual understanding and effective
preparation for cumulative course material.
1. What is the primary function of the mitotic spindle during cell division?
A) To replicate DNA
B) To separate chromosomes
C) To divide the cytoplasm
D) To synthesize proteins
Answer: B
Rationale: The mitotic spindle is a structure made of microtubules that separates
the chromosomes during mitosis by attaching to kinetochores and pulling sister
chromatids apart.
2. Which structure joins sister chromatids together?
A) Centrosome
B) Kinetochore
C) Centromere
D) Spindle fiber
Answer: C
Rationale: The centromere is the region of a chromosome where the two sister
chromatids are joined together after DNA replication.
,3. What type of cells contain two complete sets of chromosomes?
A) Haploid cells
B) Gametes
C) Diploid cells
D) Germ cells
Answer: C
Rationale: Diploid cells contain two complete sets of chromosomes, one inherited
from each parent.
4. Which process contributes to genetic diversity by exchanging genetic material
between homologous chromosomes?
A) Independent assortment
B) Crossing over
C) Cytokinesis
D) DNA replication
Answer: B
Rationale: Crossing over is the exchange of genetic material between homologous
chromosomes during meiosis, contributing to genetic diversity.
5. What is the primary component of cell membranes?
A) Protein bilayer
B) Phospholipid bilayer
C) Carbohydrate layer
D) Nucleic acid layer
Answer: B
Rationale: The cell membrane is composed of a phospholipid bilayer with
embedded proteins, forming a semi-permeable barrier around the cell.
6. Which level of biological organization includes multiple interacting
populations?
A) Community
B) Ecosystem
C) Organism
D) Tissue
Answer: A
Rationale: A community consists of all the populations of different species that
interact in a particular area.
7. What is the atomic number of an element?
A) The number of neutrons in the nucleus
,B) The number of protons in the nucleus
C) The total number of protons and neutrons
D) The number of electrons in the outer shell
Answer: B
Rationale: The atomic number is the number of protons present in the nucleus of
an atom.
8. Which elements account for approximately 90% of all living matter?
A) Calcium, Phosphorus, Potassium, Sulfur
B) Carbon, Oxygen, Hydrogen, Nitrogen
C) Iron, Magnesium, Sodium, Chlorine
D) Zinc, Copper, Manganese, Boron
Answer: B
Rationale: Carbon, Oxygen, Hydrogen, and Nitrogen account for 90% of all living
things.
9. What is an ion?
A) A neutral atom
B) An electrically charged atom or molecule
C) A molecule with covalent bonds
D) A substance with no charge
Answer: B
Rationale: An ion is an electrically charged atom or molecule formed by the loss or
gain of electrons.
10. What is the function of guard cells in plants?
A) To absorb water from soil
B) To control transpiration by opening and closing stomata
C) To transport nutrients through the plant
D) To produce chlorophyll
Answer: B
Rationale: Guard cells control transpiration by opening and closing stomata,
regulating water loss and gas exchange.
11. What is the Casparian strip and what does it do?
A) A protein that binds to DNA
B) A waxy barrier that stops water and solutes from entering the xylem through
cell walls
C) A type of plant hormone
D) A structure that stores energy
, Answer: B
Rationale: The Casparian strip is a continuous waxy barrier that forces water and
solutes to cross a plasma membrane into an endodermal cell, regulating mineral
uptake.
12. What pulls water up xylem vessels?
A) Root pressure only
B) Transpiration
C) Active transport
D) Osmosis
Answer: B
Rationale: Transpiration pulls water up xylem vessels by creating a vacuum in
leaves when water exits through stomata.
13. What is xylem sap composed of?
A) Sugar and amino acids
B) Water and minerals
C) Hormones and enzymes
D) Lipids and proteins
Answer: B
Rationale: Xylem sap is composed of water and minerals transported in xylem
vessels.
14. What type of tissue forms sheets of closely packed cells that cover body
surfaces?
A) Connective tissue
B) Muscle tissue
C) Nervous tissue
D) Epithelial tissue
Answer: D
Rationale: Epithelial tissues are sheets of closely packed cells that cover body
surfaces and line internal organs and cavities, functioning as protective barriers.
15. What is the basal lamina?
A) A type of muscle cell
B) A dense mat of extracellular matrix that separates epithelium from underlying
tissues
C) A component of the nervous system
D) A structure found in plant cells
Answer: B