BIOD 101 MODULE 1–6 & FINAL EXAM – 2026-2027 | PORTAGE LEARNING |
COMPLETE VERIFIED Q&AS + REVIEW GUIDE
1. Which of the following best describes the relationship between structure and function in
human biology?
A. Structure always determines function.
B. Function determines structure.
C. There is no relationship between structure and function.
D. Structure and function are unrelated in living systems.
Answer: A. Structure always determines function.
Rationale: The anatomy (structure) of cells, tissues, and organs directly influences their
physiology (function). For instance, the thin alveolar walls allow efficient gas exchange.
2. Which of the following is a correct example of homeostasis?
A. Blood glucose rising after eating.
B. Shivering when body temperature drops.
C. Heart rate increasing during exercise.
D. Sweating when body temperature falls.
Answer: B. Shivering when body temperature drops.
Rationale: Shivering generates heat via muscle contractions, restoring temperature balance — a
homeostatic response.
3. The cell membrane’s selective permeability is primarily due to:
A. DNA and RNA components.
B. Phospholipid bilayer with embedded proteins.
C. Presence of lysosomes.
D. Ribosomal enzymes.
Answer: B. Phospholipid bilayer with embedded proteins.
Rationale: The hydrophobic lipid tails restrict passage of polar molecules, while proteins act as
transporters for selective permeability.
,4. Mitochondria are often called the “powerhouse” of the cell because they:
A. Store calcium ions.
B. Produce ATP through cellular respiration.
C. Control gene expression.
D. Break down waste.
Answer: B. Produce ATP through cellular respiration.
Rationale: Mitochondria convert glucose and oxygen into ATP, the cell’s main energy currency.
5. Which of the following organ systems is primarily responsible for gas exchange?
A. Digestive
B. Circulatory
C. Respiratory
D. Nervous
Answer: C. Respiratory.
Rationale: The respiratory system enables oxygen intake and carbon dioxide removal through
the alveoli.
6. In negative feedback regulation, the response of the system:
A. Reinforces the original stimulus.
B. Cancels the original stimulus.
C. Has no effect on the stimulus.
D. Causes instability.
Answer: B. Cancels the original stimulus.
Rationale: Negative feedback mechanisms restore balance by counteracting deviations (e.g.,
insulin lowers high blood glucose).
7. The process by which water moves across a membrane from low to high solute concentration
is called:
A. Diffusion
B. Osmosis
C. Active transport
D. Filtration
Answer: B. Osmosis.
Rationale: Osmosis is passive water movement through a semi-permeable membrane toward
higher solute concentration.
,8. Which macromolecule serves as the main source of quick energy for cells?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic acids
Answer: C. Carbohydrates.
Rationale: Glucose, a carbohydrate, is the body’s preferred energy molecule used in glycolysis
and cellular respiration.
9. DNA replication occurs during which phase of the cell cycle?
A. G₁ phase
B. S phase
C. G₂ phase
D. M phase
Answer: B. S phase.
Rationale: The synthesis (S) phase ensures each daughter cell receives an identical copy of
genetic material.
10. Which type of tissue is responsible for generating electrical impulses?
A. Connective tissue
B. Nervous tissue
C. Muscle tissue
D. Epithelial tissue
Answer: B. Nervous tissue.
Rationale: Neurons transmit electrical signals that regulate body functions and communication.
11. The smallest structural and functional unit of life is the:
A. Atom
B. Molecule
C. Organelle
D. Cell
Answer: D. Cell.
Rationale: All living organisms are composed of one or more cells — the basic unit of structure
and function.
, 12. Which organ filters and detoxifies chemicals and drugs in the body?
A. Liver
B. Kidney
C. Pancreas
D. Spleen
Answer: A. Liver.
Rationale: Hepatocytes in the liver metabolize toxins and drugs through enzymatic pathways.
13. Which of the following best represents a catabolic reaction?
A. Building muscle protein from amino acids
B. Synthesizing glycogen from glucose
C. Breaking down glucose into pyruvate
D. Forming DNA from nucleotides
Answer: C. Breaking down glucose into pyruvate.
Rationale: Catabolism involves breaking larger molecules into smaller ones, releasing energy.
14. The genetic code is carried by:
A. rRNA
B. mRNA
C. tRNA
D. DNA polymerase
Answer: B. mRNA.
Rationale: Messenger RNA carries the transcribed genetic code from DNA to ribosomes for
protein synthesis.
15. What structure separates the thoracic cavity from the abdominal cavity?
A. Pleura
B. Diaphragm
C. Pericardium
D. Mediastinum
Answer: B. Diaphragm.
Rationale: The diaphragm is a dome-shaped muscle that aids in breathing and divides the two
cavities.
16. Which element is most abundant in the human body?
A. Nitrogen
COMPLETE VERIFIED Q&AS + REVIEW GUIDE
1. Which of the following best describes the relationship between structure and function in
human biology?
A. Structure always determines function.
B. Function determines structure.
C. There is no relationship between structure and function.
D. Structure and function are unrelated in living systems.
Answer: A. Structure always determines function.
Rationale: The anatomy (structure) of cells, tissues, and organs directly influences their
physiology (function). For instance, the thin alveolar walls allow efficient gas exchange.
2. Which of the following is a correct example of homeostasis?
A. Blood glucose rising after eating.
B. Shivering when body temperature drops.
C. Heart rate increasing during exercise.
D. Sweating when body temperature falls.
Answer: B. Shivering when body temperature drops.
Rationale: Shivering generates heat via muscle contractions, restoring temperature balance — a
homeostatic response.
3. The cell membrane’s selective permeability is primarily due to:
A. DNA and RNA components.
B. Phospholipid bilayer with embedded proteins.
C. Presence of lysosomes.
D. Ribosomal enzymes.
Answer: B. Phospholipid bilayer with embedded proteins.
Rationale: The hydrophobic lipid tails restrict passage of polar molecules, while proteins act as
transporters for selective permeability.
,4. Mitochondria are often called the “powerhouse” of the cell because they:
A. Store calcium ions.
B. Produce ATP through cellular respiration.
C. Control gene expression.
D. Break down waste.
Answer: B. Produce ATP through cellular respiration.
Rationale: Mitochondria convert glucose and oxygen into ATP, the cell’s main energy currency.
5. Which of the following organ systems is primarily responsible for gas exchange?
A. Digestive
B. Circulatory
C. Respiratory
D. Nervous
Answer: C. Respiratory.
Rationale: The respiratory system enables oxygen intake and carbon dioxide removal through
the alveoli.
6. In negative feedback regulation, the response of the system:
A. Reinforces the original stimulus.
B. Cancels the original stimulus.
C. Has no effect on the stimulus.
D. Causes instability.
Answer: B. Cancels the original stimulus.
Rationale: Negative feedback mechanisms restore balance by counteracting deviations (e.g.,
insulin lowers high blood glucose).
7. The process by which water moves across a membrane from low to high solute concentration
is called:
A. Diffusion
B. Osmosis
C. Active transport
D. Filtration
Answer: B. Osmosis.
Rationale: Osmosis is passive water movement through a semi-permeable membrane toward
higher solute concentration.
,8. Which macromolecule serves as the main source of quick energy for cells?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic acids
Answer: C. Carbohydrates.
Rationale: Glucose, a carbohydrate, is the body’s preferred energy molecule used in glycolysis
and cellular respiration.
9. DNA replication occurs during which phase of the cell cycle?
A. G₁ phase
B. S phase
C. G₂ phase
D. M phase
Answer: B. S phase.
Rationale: The synthesis (S) phase ensures each daughter cell receives an identical copy of
genetic material.
10. Which type of tissue is responsible for generating electrical impulses?
A. Connective tissue
B. Nervous tissue
C. Muscle tissue
D. Epithelial tissue
Answer: B. Nervous tissue.
Rationale: Neurons transmit electrical signals that regulate body functions and communication.
11. The smallest structural and functional unit of life is the:
A. Atom
B. Molecule
C. Organelle
D. Cell
Answer: D. Cell.
Rationale: All living organisms are composed of one or more cells — the basic unit of structure
and function.
, 12. Which organ filters and detoxifies chemicals and drugs in the body?
A. Liver
B. Kidney
C. Pancreas
D. Spleen
Answer: A. Liver.
Rationale: Hepatocytes in the liver metabolize toxins and drugs through enzymatic pathways.
13. Which of the following best represents a catabolic reaction?
A. Building muscle protein from amino acids
B. Synthesizing glycogen from glucose
C. Breaking down glucose into pyruvate
D. Forming DNA from nucleotides
Answer: C. Breaking down glucose into pyruvate.
Rationale: Catabolism involves breaking larger molecules into smaller ones, releasing energy.
14. The genetic code is carried by:
A. rRNA
B. mRNA
C. tRNA
D. DNA polymerase
Answer: B. mRNA.
Rationale: Messenger RNA carries the transcribed genetic code from DNA to ribosomes for
protein synthesis.
15. What structure separates the thoracic cavity from the abdominal cavity?
A. Pleura
B. Diaphragm
C. Pericardium
D. Mediastinum
Answer: B. Diaphragm.
Rationale: The diaphragm is a dome-shaped muscle that aids in breathing and divides the two
cavities.
16. Which element is most abundant in the human body?
A. Nitrogen
