BIOD 102 Cumulative Final Exam Portage Learning Questions
and Answers 2026
Module 1 & 2: Molecular Biology & Signaling (1–10)
1. Which enzyme is responsible for sealing the "nicks" between Okazaki fragments
on the lagging strand?
• A) Helicase
• B) DNA Polymerase I
• C) DNA Ligase
• D) Primase
• Rationale: Ligase acts as the "glue" that creates a continuous sugar-phosphate
backbone after replication.
2. In the "Central Dogma," the process of making mRNA from a DNA template is:
• A) Replication
• B) Transcription
• C) Translation
• D) Transformation
• Rationale: Transcription occurs in the nucleus where DNA is transcribed into
messenger RNA.
3. Which type of point mutation results in a premature "stop" codon?
• A) Silent
• B) Missense
• C) Nonsense
• D) Frameshift
• Rationale: A nonsense mutation truncates the protein, usually rendering it non-
functional.
,4. A hormone that acts on the same cell that secreted it is using:
• A) Autocrine signaling
• B) Paracrine signaling
• C) Endocrine signaling
• D) Synaptic signaling
• Rationale: "Auto" means self; the cell stimulates itself.
5. Steroid hormones are lipid-soluble, meaning their receptors are typically found:
• A) On the plasma membrane
• B) Inside the cytoplasm or nucleus
• C) On the ribosome
• D) In the Golgi apparatus
• Rationale: Being hydrophobic, steroids diffuse through the membrane to bind to
internal receptors.
6. Which protein wraps around DNA to help package it into chromatin?
• A) Tubulin
• B) Actin
• C) Histones
• D) Keratin
• Rationale: Histones are positively charged proteins that attract negatively
charged DNA.
7. The "Poly-A Tail" added to mRNA functions to:
• A) Start translation
• B) Protect the mRNA from degradation in the cytoplasm
• C) Code for amino acids
• D) Fold the protein
, • Rationale: It increases the stability and lifespan of the mRNA molecule.
8. Which signaling molecule is used by the Nervous System for rapid, short-
distance communication?
• A) Hormone
• B) Neurotransmitter
• C) Pheromone
• D) Vitamin
• Rationale: Neurotransmitters cross the synaptic cleft to reach the immediate
post-synaptic cell.
9. Introns are:
• A) Expressed sequences of DNA
• B) Non-coding sequences that are spliced out of mRNA
• C) Enzymes that build DNA
• D) Types of bacteria
• Rationale: "In-trons" stay "In" the nucleus (removed); "Ex-ons" "Exit" to be
expressed.
10. The secondary messenger cAMP is frequently activated by:
• A) DNA Polymerase
• B) G-protein coupled receptors (GPCRs)
• C) The Sodium-Potassium pump
• D) Myosin
• Rationale: GPCRs activate adenylyl cyclase, which converts ATP to cAMP.
Module 3: Nerve & Muscle Physiology (11–20)
11. During the "Rising Phase" of an action potential:
• A) K+ rushes out
, • B) Na+ rushes in
• C) Cl- rushes in
• D) The pump stops
• Rationale: Voltage-gated sodium channels open, causing rapid depolarization.
12. The gap between a motor neuron and a muscle fiber is the:
• A) Synapse
• B) Neuromuscular Junction (NMJ)
• C) Sarcomere
• D) Node of Ranvier
• Rationale: This is the specific chemical synapse where nerve meets muscle.
13. Myosin heads pull on actin filaments during the:
• A) Latent period
• B) Power stroke
• C) Relaxation phase
• D) Repolarization
• Rationale: The power stroke is the actual mechanical movement of the
contraction.
14. Which structure stores Calcium in the muscle cell?
• A) Mitochondria
• B) Sarcoplasmic Reticulum
• C) T-tubules
• D) Nucleus
• Rationale: The SR releases Ca2+ in response to an electrical signal.
15. Saltatory conduction occurs in:
and Answers 2026
Module 1 & 2: Molecular Biology & Signaling (1–10)
1. Which enzyme is responsible for sealing the "nicks" between Okazaki fragments
on the lagging strand?
• A) Helicase
• B) DNA Polymerase I
• C) DNA Ligase
• D) Primase
• Rationale: Ligase acts as the "glue" that creates a continuous sugar-phosphate
backbone after replication.
2. In the "Central Dogma," the process of making mRNA from a DNA template is:
• A) Replication
• B) Transcription
• C) Translation
• D) Transformation
• Rationale: Transcription occurs in the nucleus where DNA is transcribed into
messenger RNA.
3. Which type of point mutation results in a premature "stop" codon?
• A) Silent
• B) Missense
• C) Nonsense
• D) Frameshift
• Rationale: A nonsense mutation truncates the protein, usually rendering it non-
functional.
,4. A hormone that acts on the same cell that secreted it is using:
• A) Autocrine signaling
• B) Paracrine signaling
• C) Endocrine signaling
• D) Synaptic signaling
• Rationale: "Auto" means self; the cell stimulates itself.
5. Steroid hormones are lipid-soluble, meaning their receptors are typically found:
• A) On the plasma membrane
• B) Inside the cytoplasm or nucleus
• C) On the ribosome
• D) In the Golgi apparatus
• Rationale: Being hydrophobic, steroids diffuse through the membrane to bind to
internal receptors.
6. Which protein wraps around DNA to help package it into chromatin?
• A) Tubulin
• B) Actin
• C) Histones
• D) Keratin
• Rationale: Histones are positively charged proteins that attract negatively
charged DNA.
7. The "Poly-A Tail" added to mRNA functions to:
• A) Start translation
• B) Protect the mRNA from degradation in the cytoplasm
• C) Code for amino acids
• D) Fold the protein
, • Rationale: It increases the stability and lifespan of the mRNA molecule.
8. Which signaling molecule is used by the Nervous System for rapid, short-
distance communication?
• A) Hormone
• B) Neurotransmitter
• C) Pheromone
• D) Vitamin
• Rationale: Neurotransmitters cross the synaptic cleft to reach the immediate
post-synaptic cell.
9. Introns are:
• A) Expressed sequences of DNA
• B) Non-coding sequences that are spliced out of mRNA
• C) Enzymes that build DNA
• D) Types of bacteria
• Rationale: "In-trons" stay "In" the nucleus (removed); "Ex-ons" "Exit" to be
expressed.
10. The secondary messenger cAMP is frequently activated by:
• A) DNA Polymerase
• B) G-protein coupled receptors (GPCRs)
• C) The Sodium-Potassium pump
• D) Myosin
• Rationale: GPCRs activate adenylyl cyclase, which converts ATP to cAMP.
Module 3: Nerve & Muscle Physiology (11–20)
11. During the "Rising Phase" of an action potential:
• A) K+ rushes out
, • B) Na+ rushes in
• C) Cl- rushes in
• D) The pump stops
• Rationale: Voltage-gated sodium channels open, causing rapid depolarization.
12. The gap between a motor neuron and a muscle fiber is the:
• A) Synapse
• B) Neuromuscular Junction (NMJ)
• C) Sarcomere
• D) Node of Ranvier
• Rationale: This is the specific chemical synapse where nerve meets muscle.
13. Myosin heads pull on actin filaments during the:
• A) Latent period
• B) Power stroke
• C) Relaxation phase
• D) Repolarization
• Rationale: The power stroke is the actual mechanical movement of the
contraction.
14. Which structure stores Calcium in the muscle cell?
• A) Mitochondria
• B) Sarcoplasmic Reticulum
• C) T-tubules
• D) Nucleus
• Rationale: The SR releases Ca2+ in response to an electrical signal.
15. Saltatory conduction occurs in:
