EduNinja

IGCSE Biology12.3 Anaerobic respirationQuestion Bank

12.3 Anaerobic respiration

Question 1

[Maximum number: 3]

Fungal cells and plant cells contain mitochondria.

Question 1(b)

(a)

Yeast is a fungus that can respire to produce ethanol.

State the balanced chemical equation for this type of respiration in yeast.

[ 2 ]

Question 1(c)

(b)

A scientist investigated the effect of sugar on respiration in yeast cells.

One flask contained 100 cm3100 \mathrm{~cm}^{3} of a sugar solution and another flask contained 100 cm3100 \mathrm{~cm}^{3} of water. Both flasks contained the same mass of yeast. The temperature was maintained at 25∘C25^{\circ} \mathrm{C}.

The scientist used the apparatus shown in Fig. 1.1.

Fig. 1.1

Fig. 1.1

ig. 1.2 is a graph of the results of the investigation.

ig. 1.2 is a graph of the results of the investigation.

[ 1 ]

Question 1(c)(iii)

(i)

State one reason why no more carbon dioxide gas was produced after 35 minutes by the yeast in a sugar solution, shown in Fig. 1.2.

[ 1 ]

Question 1

[Maximum number: 1]

Wheat is a crop plant grown to produce flour.

Question 1(a)

(a)

Flour is used to make dough for bread.

[ 1 ]

Question 1(a)(ii)

(i)

State the name of the process that this organism uses to produce the gas that makes dough rise.

[ 1 ]

Question 1

Question 1(c)

(a)

Describe the role of the liver in the recovery from oxygen debt after strenuous exercise.

[ 2 ]

Question 2

[Maximum number: 1]

Fig. 2.1 shows a cross-section of a human heart.

Fig. 2.1

Fig. 2.1

Question 2(c)

(a)

Fig. 2.3 shows how the body uses aerobic and anaerobic respiration during the first 120 seconds of vigorous physical activity. Between 0 and 20 seconds, the body also uses stored energy.
percentage of energy released

Fig. 2.3

Fig. 2.3

[ 1 ]

Question 2(c)(iii)

(i)

During anaerobic respiration an oxygen debt can build up.

State the name of the chemical that causes this oxygen debt.

[ 1 ]

Question 2

[Maximum number: 8]

A person who wanted to begin a fitness programme did some vigorous exercise.
A fitness trainer took a drop of blood from the person's finger before, during and after vigorous exercise and tested it for lactic acid.

Question 2(b)

(a)

The results of the tests for lactic acid are shown in Fig. 2.1.

Fig. 2.1

Fig. 2.1

Describe and explain the changes in blood lactic acid concentration shown in Fig. 2.1.

[ 6 ]

Question 2(c)

(b)

The concentration of lactic acid in the blood of two athletes was investigated. One athlete, P, had been training and the other, Q, was returning to training after an injury.

Blood samples were taken from both athletes during a training session. The results are shown in Fig. 2.2.

Fig. 2.2

Fig. 2.2

[ 2 ]

Question 2(c)(i)

(i)

The lactic acid threshold is the level of exercise where the lactic acid concentration begins to increase exponentially.

State the lactic acid threshold for athletes P and Q.
P kmh−1\mathrm{km} \mathrm{h}^{-1}

Q kmh−1\mathrm{km} \mathrm{h}^{-1}

[ 1 ]

Question 2(c)(ii)

(ii)

Suggest a reason for the difference in lactic acid threshold of athletes P and Q.

[ 1 ]

Question 17

[Maximum number: 1]

The table shows some of the features of respiration.
Which row is correct for anaerobic respiration?

amount of energy
released per
glucose molecule

chemical reaction

releases
carbon dioxide

high

always the same

sometimes

low

different in different organisms

sometimes

high

different in different organisms

always

low

always the same

always

Question 3

[Maximum number: 6]

Yeast is used in bread-making. It respires anaerobically, producing carbon dioxide.

Question 3(a)

(a)

Write the balanced chemical equation for anaerobic respiration of yeast in bread-making.

[ 2 ]

Question 3(b)

(b)

A baker wants to increase the rate of carbon dioxide production in the bread-making process. The baker trialled different concentrations of glucose solution in the bread dough.
Fig. 3.1 shows the results.

Fig. 3.1

Fig. 3.1

[ 4 ]

Question 3(b)(i)

(i)

Predict the rate of carbon dioxide production if the concentration of the glucose solution was 7.0 %. cm3\mathrm{cm}^{3} per min

[ 1 ]

Question 3(b)(ii)

(ii)

The baker carried out the trials at 30∘C30^{\circ} \mathrm{C}.

The trials were repeated at 20∘C20^{\circ} \mathrm{C}.
Draw a line on Fig. 3.1 to show the rate of carbon dioxide production at 20∘C20^{\circ} \mathrm{C}.

[ 2 ]

Question 3(b)(iii)

(iii)

The baker carried out another trial at 80∘C80^{\circ} \mathrm{C}. No carbon dioxide was released.

State why no carbon dioxide was produced.

[ 1 ]

Question 18

[Maximum number: 1]

The diagram shows some apparatus used to investigate respiration. Yeast, warm water and substance Z were put into a test-tube. After a while, the limewater began to go cloudy.

Question image

What is substance Z ?

A

alcohol

B

glucose

C

nitrogen

D

oxygen

Question 20

[Maximum number: 1]

What are the products of anaerobic respiration in muscles?

A

ethanol and carbon dioxide

B

ethanol only

C

lactic acid and carbon dioxide

D

lactic acid only

Question 21

[Maximum number: 1]

Yeast is able to respire both aerobically and anaerobically.
Which statement describes the waste products of yeast respiration?

A

Aerobic respiration produces alcohol as one of its waste products.

B

Aerobic respiration produces three times as much carbon dioxide as anaerobic respiration from one molecule of glucose.

C

Anaerobic respiration and aerobic respiration both produce the same amount of carbon dioxide from one molecule of glucose.

D

Anaerobic respiration produces three times as much carbon dioxide as aerobic respiration from one molecule of glucose.

0 selected