Week 4 — Quiz (auto-graded) · Cellular Metabolism & Protein Synthesis

Course: Anatomy & Physiology I (BIOL 2301 + BIOL 2101) · Silver Oak University (fictional sample) · Prof. Navarro
Objective tested: Objective 2 — ATP as energy currency; cellular respiration (the three stages in order, locations, where the most ATP is made); aerobic vs. anaerobic; the central dogma (transcription, translation, the codon); why protein synthesis matters.
Points: 10 (1 each) · Assignment group: Quizzes (10% of grade) · Due: end of Module 4.

This is the human-readable quiz with its vetted answer key and feedback. The import-ready Classic QTI is in F-quiz-week-04-qti.xml (generated by the shared validated script — parses with 10 items, every single-answer item exactly one correct). The reusable item-bank entries and the Canvas placement block are at the bottom of this file.

Blueprint

No trick questions; distractors target the Week 4 misconceptions named in the lecture outline (stage order, "most ATP" location, ATP-as-battery, oxygen's role, nucleus vs. mitochondria, transcription vs. translation). Item 3 is the required sequence/ordering-via-matching item (respiration stages, in order); Item 8 is the true/false item.

Questions, key, and feedback

Q1 (MC). Which statement best describes the role of ATP (adenosine triphosphate) in the cell?
- A. It is the cell's immediate energy currency; energy is released when the bond to its third phosphate breaks, forming ADP + Pi ✅
- B. It is a long-term energy battery the cell stores for weeks and slowly drains
- C. It is the molecule that stores the cell's genetic information
- D. It is the final electron acceptor at the end of cellular respiration
Feedback: ATP is spendable energy "cash," not a battery — breaking the third phosphate bond releases usable energy and leaves ADP + an inorganic phosphate (Pi). Cells store very little ATP and remake it constantly. (B confuses it with long-term storage like fat/glycogen; C describes DNA; D describes oxygen's role.)

Q2 (MC). Which equation best summarizes aerobic cellular respiration?
- A. carbon dioxide + water → glucose + oxygen
- B. glucose + oxygen → carbon dioxide + water + ATP ✅
- C. glucose → DNA + protein
- D. oxygen + protein → ATP + water
Feedback: A cell "burns" glucose with oxygen in controlled steps, releasing carbon dioxide + water and capturing energy as ATP. (A is the reverse — that's photosynthesis; C and D mix up unrelated molecules.)

Q3 (Matching — stages in order). Cellular respiration happens in three stages, in order. Match each stage to where it happens and its key output. (Stage 1 = glycolysis, Stage 2 = citric acid / Krebs cycle, Stage 3 = electron transport chain.)
| Stage | Correct location & output |
|---|---|
| Stage 1 (FIRST) — Glycolysis | Cytoplasm (cytosol): glucose is split into 2 pyruvate; small amount of ATP |
| Stage 2 (SECOND) — Citric acid (Krebs) cycle | Mitochondrial matrix: carbon dioxide is released; electron carriers are loaded |
| Stage 3 (LAST) — Electron transport chain | Inner mitochondrial membrane: the MOST ATP is made |
| Final electron acceptor in Stage 3 | Oxygen (it accepts the spent electrons and helps form water) |
Feedback: The order is glycolysis (cytoplasm) → Krebs cycle (matrix) → electron transport chain (inner membrane). Glycolysis is first and needs no oxygen; the Krebs cycle releases the CO₂ you exhale; the ETC makes the most ATP, with oxygen as the final electron acceptor.

Q4 (MC). In aerobic cellular respiration, which stage produces the MOST ATP, and what is the role of oxygen?
- A. Glycolysis produces the most ATP; oxygen is split apart for fuel
- B. The Krebs cycle produces the most ATP; oxygen is not involved
- C. The electron transport chain produces the most ATP; oxygen is the final electron acceptor ✅
- D. All three stages produce equal ATP; oxygen donates electrons to glucose
Feedback: The electron transport chain makes the most ATP, by far. Oxygen is not "broken down for fuel" — it is the final electron acceptor at the end of the chain, forming water. Glucose is the fuel; oxygen is the electron catcher. (A and D misstate oxygen's role; B wrongly credits the Krebs cycle.)

Q5 (MC). TRANSCRIPTION is best described as:
- A. Copying DNA into messenger RNA (mRNA), which takes place in the nucleus ✅
- B. Reading mRNA to build a protein, which takes place at the ribosome
- C. Breaking down glucose to release ATP in the cytoplasm
- D. Pumping sodium and potassium across the cell membrane
Feedback: Transcription = DNA → mRNA, in the nucleus ("traNscription happens in the Nucleus and makes RNA"). Option B describes translation; C is glycolysis; D is the Na⁺/K⁺ pump.

Q6 (MC). TRANSLATION is best described as:
- A. Copying DNA into mRNA inside the nucleus
- B. Reading mRNA to assemble a chain of amino acids (a protein) at the ribosome ✅
- C. Splitting one glucose molecule into two pyruvate molecules
- D. Storing genetic information in the form of DNA
Feedback: Translation = mRNA → protein, at the ribosome — the ribosome reads codons and strings together amino acids. Option A is transcription (the two are swapped constantly — anchor each to what goes in and what comes out); C is glycolysis; D describes DNA's job.

Q7 (Multiple answer — select all that apply). Which of the following statements about cellular respiration are TRUE?
- A. The electron transport chain requires oxygen as the final electron acceptor ✅
- B. Aerobic respiration (with oxygen) yields much more ATP than anaerobic fermentation ✅
- C. During a hard sprint, muscle cells can rely on glycolysis without oxygen and produce lactic acid ✅
- D. Glycolysis takes place inside the mitochondrial matrix
- E. The nucleus is where most of the cell's ATP is produced
Feedback: True: the ETC needs oxygen as the final acceptor (A); aerobic yields far more ATP than fermentation (B); a sprint drives anaerobic glycolysis → lactic acid (C). False distractors: glycolysis is in the cytoplasm, not the matrix (D); the mitochondria, not the nucleus, make most ATP (E).

Q8 (True / False). "The nucleus produces most of the cell's ATP."
- True
- False ✅
Feedback: False. The mitochondria produce most of the cell's ATP (the Krebs cycle in the matrix and the electron transport chain on the inner membrane). The nucleus stores DNA — it's the cell's control center, not its power plant.

Q9 (MC). What is a codon, and what does it specify?
- A. A single mRNA base that specifies one whole protein
- B. A group of three mRNA bases that specifies one amino acid ✅
- C. A group of three proteins that specifies one gene
- D. A single DNA base that specifies one codon
Feedback: A codon = 3 mRNA bases = 1 amino acid. The ribosome reads mRNA in three-letter "words." (One base couldn't code for the ~20 amino acids — only four single letters exist; triplets give plenty. A, C, and D scramble the units.)

Q10 (MC). Why does protein synthesis matter for anatomy and physiology?
- A. Because proteins (enzymes, membrane channels, and structural fibers like actin and collagen) do the actual work of the body, so building them builds the machinery of every system ✅
- B. Because proteins are the cell's main long-term energy store
- C. Because proteins are the final electron acceptor in respiration
- D. Because protein synthesis only matters for genetics, not for body systems
Feedback: Proteins are the body's workers — enzymes speed reactions, channels move ions (the Na⁺/K⁺ pump), and actin/myosin/collagen build muscle, skin, and bone. So protein synthesis builds the machinery of every system (structure → function). (B is fat/glycogen; C is oxygen; D is exactly the misconception the week corrects.)

Answer key (quick reference)

Quality gate (self-checked): each single-answer item has exactly one correct option; the multiple-answer item (Q7) keys the three true statements (A, B, C) and requires the two false distractors (D glycolysis-in-matrix, E nucleus-makes-ATP) to be left unselected; the sequence/ordering matching item (Q3) pairs the three respiration stages and the final-acceptor line to four distinct, correctly ordered location/output cells. Accuracy gate — process ordering: verified. Cellular respiration order = glycolysis (cytoplasm) → citric acid/Krebs cycle (matrix) → electron transport chain (inner membrane), with the most ATP made in the ETC and oxygen as the final electron acceptor; central dogma order = DNA → transcription → mRNA → translation → protein, with codon = 3 mRNA bases = 1 amino acid; transcription (DNA→mRNA, nucleus) vs. translation (mRNA→protein, ribosome) kept distinct. Anatomy-accuracy gate: PASS. Quantitative gate: does not apply this week (Week 4 is an overview process week with no curriculum arithmetic in the quiz; the codon-decoding accuracy check lives in Lab 4, where it is Python-verified).

Item-bank entries (for variants + the midterm/final)

All ten items are tagged course=BIOL2301 · week=4 · objective=2 · topic=metabolism-protein-synthesis and deposited in Item Bank: Week 4 — Cellular Metabolism & Protein Synthesis. The midterm (Week 8) and the per-term variant updates draw fresh items from this bank. (Tags: q1 atp-currency, q2 respiration-equation, q3 respiration-stages-order, q4 etc-most-atp-oxygen, q5 transcription, q6 translation, q7 aerobic-anaerobic-select, q8 nucleus-atp-misconception, q9 codon, q10 why-proteins-matter.)

Canvas placement block

canvas_object   = Quizzes::Quiz
title           = "Week 4 Quiz — Cellular Metabolism & Protein Synthesis"
assignment_group = "Quizzes"
points_possible = 10
grading_type    = points
due_offset_days = 6        # 6 days after module start
published       = true
shuffle_answers = true
provenance      = "~ Prof. Navarro's edition · Fall 2026 · built with thecoursemaker.com"