Pupil sheet · Respiration
Respiration — return questions
Name ______________________ Date ____________
Use one to two weeks after the lessons. Keep the notes and the lesson closed.
1. describe
A cell in the root of a carrot plant, in damp, airy soil, releases energy from glucose. Describe the process.
2. identify
A locust is kept in a sealed glass jar for an hour, and the air in the jar is tested before and after. Use the word equation for aerobic respiration to identify (1) the gas that decreased, (2) the gas that increased and turns limewater milky, and (3) the nutrient that the locust's cells broke down.
(1) The gas that decreased
(2) The gas that increased
(3) The nutrient broken down
3. state
A dolphin swims in cold sea water. State the use of energy in each of these. (a) Its tail muscles shorten to push it forward. (b) Its body stays at about 36 °C. (c) A signal travels along a nerve from its ear to its brain. (d) Its skin cells divide to replace old cells.
(a) Tail muscles
(b) 36 °C
(c) Ear to brain
(d) New skin cells
4. state
Supplement. State the balanced chemical equation for aerobic respiration.
5. explain
A pupil writes: "Anaerobic respiration releases energy without using any food, and it releases more energy than aerobic respiration, because no oxygen is needed." Explain why (a) "without using any food" and (b) "more energy" are incorrect.
(a) "Without using any food"
(b) "More energy"
6. state
State the word equation for anaerobic respiration in yeast: fill in its three substances.
… →
… +
…
7. calculate
Yeast at 28 °C gives off gas at a steady rate of 1.8 cm³ per minute. The gas syringe reads 6 cm³ when the clock starts. Calculate (a) the volume of gas collected in 5 minutes, and (b) the syringe reading after 5 minutes.
(a) Volume of gas collected in 5 minutes: ______________ unit ________
(b) Syringe reading after 5 minutes: ______________ unit ________
8. state
Supplement. State the balanced chemical equation for anaerobic respiration in yeast.
9. identify
Which row shows the products of each kind of respiration?
| Row | Aerobic respiration | Anaerobic respiration in muscles | Anaerobic respiration in yeast |
|---|---|---|---|
| A | carbon dioxide and water | lactic acid and carbon dioxide | alcohol and carbon dioxide |
| B | carbon dioxide and water | alcohol and carbon dioxide | lactic acid |
| C | oxygen and water | lactic acid | alcohol and carbon dioxide |
| D | carbon dioxide and water | lactic acid | alcohol and carbon dioxide |
Circle one answer.
- A
- B
- C
- D
10. explain
Supplement. Explain what causes an oxygen debt.
11. explain
Supplement. (a) A footballer walks onto the pitch with a heart rate of 75 beats per minute. During a long sprint it reaches 170. Explain why her heart rate rises. (b) After the match, a pupil writes: "The lactic acid in her blood is breathed out by her lungs." Explain why this is incorrect.
(a) Why the heart rate rises
(b) Why the statement is incorrect