Respiration without oxygen

Question 1

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 2

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 3 cm³ 20 °C: 6 cm³ 30 °C: 11 cm³ 40 °C: 26 cm³ 50 °C: 2 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 3

Why does anaerobic respiration release less energy than aerobic respiration?

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

Question 4

Which word equation shows the respiration happening here: a sprinter's leg muscles in a 100 m race?

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

Question 5

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 5 cm³ 20 °C: 14 cm³ 30 °C: 23 cm³ 40 °C: 13 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 6

Why does anaerobic respiration release less energy than aerobic respiration?

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

Question 7

Which word equation shows the respiration happening here: a sprinter's leg muscles in a 100 m race?

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

Question 8

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 2 cm³ 20 °C: 7 cm³ 30 °C: 13 cm³ 40 °C: 21 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 9

Why does anaerobic respiration release less energy than aerobic respiration?

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

Question 10

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 11

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 4 cm³ 20 °C: 7 cm³ 30 °C: 13 cm³ 40 °C: 22 cm³ 50 °C: 3 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 12

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

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

Question 13

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 14

Yeast was mixed with sugar solution and the gas collected in 10 minutes was measured: 10 °C: 4 cm³ 20 °C: 8 cm³ 30 °C: 14 cm³ 40 °C: 23 cm³ 50 °C: 1 cm³ At which temperature did the yeast respire fastest, in °C?

Answer °C

Question 15

Bacteria in milk respire anaerobically and make lactic acid. Which food does this produce?

• A. bread
• B. jam
• C. butter
• D. yoghurt (yogurt)

Question 16

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