12 exam-style questions (57 marks) in three tiers. Try each one on paper first, then check the model answer and mark scheme.
Chapter 6 notes12 questions · 57 marks
Showing 12 of 12 questions
Recall and simple application
Name the structures of the air pathway, in order, from the larynx to the site of gaseous exchange.
State the word equation for aerobic respiration.
State the word equation for anaerobic respiration in human muscle.
Name the three toxic components of tobacco smoke and match one effect to each.
Structured, exam-style
Explain how four structural features of the alveoli make them efficient surfaces for gaseous exchange.
A smoker's blood carries less oxygen than a non-smoker)s at the same alveolar oxygen level. Name the smoke component responsible and explain its mechanism.
Complete the comparison table for aerobic and anaerobic respiration in humans.
| Property | Aerobic | Anaerobic (human muscle) |
|---|---|---|
| oxygen used? | ________ | no |
| word equation | ________ | glucose → lactic acid (+ energy) |
| main products | carbon dioxide + water | ________ |
| when it runs | normal conditions | ________ |
Inspired air contains about 21% oxygen and 0.04% carbon dioxide; expired air contains about 16% oxygen and 4% carbon dioxide. (a) Describe the two changes. (b) Explain each using respiration. (c) State which gas is unchanged and why.
Data, evaluation and explanation
A student claims: "Breathing is respiration." Distinguish the two processes, naming the system each belongs to and linking them with the word equation.
One sphere has radius R. Eight spheres each of radius R/2 hold the same total volume. (a) Show that the eight small spheres have twice the surface area of the large one. (b) Use this result to explain why the lung divides its air space into millions of alveoli.
A 400 m runner finishes and keeps breathing rapidly and deeply for five minutes. (a) Explain why her muscles respired anaerobically during the race. (b) State the word equation for that process. (c) Explain the purpose of her post-race breathing. (d) State what would happen to her breathing if the lactic acid could not be broken down.
Design a controlled investigation to compare the oxygen and carbon dioxide content of inspired and expired air, and predict the results. (a) State how each gas would be tested. (b) State two variables to control. (c) Predict and explain the results.
Next step
A 30-mark paper set out like a school paper, with a separate mark scheme. Give yourself 40 min.
Question paper
30 marks · 40 min · 5 pages
5 multiple-choice questions and structured questions with answer lines. Chapter 6 (air pathway; alveolus adaptation; tobacco smoke toxins; aerobic and anaerobic respiration; oxygen debt).
Mark scheme
PROAnswers · Marking points · 3 pages
Model answers with a mark for each creditworthy point — for marking at home or in class.