Respiration without oxygen

Question 1

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 4 cm³ 20 °C: 6 cm³ 30 °C: 14 cm³ 40 °C: 25 cm³ 50 °C: 2 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 2

Why does anaerobic respiration release less energy than aerobic respiration?

• A. It happens in the lungs
• B. It makes more water
• C. Glucose is only partly broken down
• D. It uses more oxygen

Question 3

Which word equation shows the respiration happening here: a person walking slowly?

• A. glucose → lactic acid
• B. glucose → ethanol + carbon dioxide
• C. glucose + oxygen → carbon dioxide + water

Question 4

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 7 cm³ 20 °C: 15 cm³ 30 °C: 26 cm³ 40 °C: 14 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 5

After a hard sprint you keep breathing fast for a while. Why?

• A. To cool the lungs
• B. Because the heart has stopped
• C. To get extra oxygen to break down the lactic acid (repay the oxygen debt)
• D. To get rid of extra glucose

Question 6

Which word equation shows the respiration happening here: a person walking slowly?

• A. glucose → lactic acid
• B. glucose → ethanol + carbon dioxide
• C. glucose + oxygen → carbon dioxide + water

Question 7

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 6 cm³ 20 °C: 11 cm³ 30 °C: 22 cm³ 40 °C: 15 cm³ 50 °C: 2 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 8

After a hard sprint you keep breathing fast for a while. Why?

• A. Because the heart has stopped
• B. To get rid of extra glucose
• C. To cool the lungs
• D. To get extra oxygen to break down the lactic acid (repay the oxygen debt)

Question 9

Which word equation shows the respiration happening here: a marathon runner's muscles at a steady pace?

• A. glucose → lactic acid
• B. glucose → ethanol + carbon dioxide
• C. glucose + oxygen → carbon dioxide + water

Question 10

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 4 cm³ 20 °C: 15 cm³ 30 °C: 26 cm³ 40 °C: 13 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 11

After a hard sprint you keep breathing fast for a while. Why?

• A. To get rid of extra glucose
• B. To cool the lungs
• C. Because the heart has stopped
• D. To get extra oxygen to break down the lactic acid (repay the oxygen debt)

Question 12

Which word equation shows the respiration happening here: yeast making bread dough rise?

• A. glucose → lactic acid
• B. glucose → ethanol + carbon dioxide
• C. glucose + oxygen → carbon dioxide + water

Question 13

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 7 cm³ 20 °C: 12 cm³ 30 °C: 21 cm³ 40 °C: 14 cm³ 50 °C: 2 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 14

In bread making, which product of fermentation makes the dough rise?

• A. carbon dioxide
• B. lactic acid
• C. oxygen
• D. ethanol

Question 15

Which word equation shows the respiration happening here: muscles doing hard exercise with too little oxygen?

• A. glucose → lactic acid
• B. glucose → ethanol + carbon dioxide
• C. glucose + oxygen → carbon dioxide + water

Question 16

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 6 cm³ 20 °C: 14 cm³ 30 °C: 21 cm³ 40 °C: 14 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C