Respiration

What helps oxygen to be absorbed rapidly into the blood in the lungs?

• AAir breathed in has less oxygen than air breathed out.

• B Alveoli have thick walls and a large surface area.

• C Alveoli have thin walls and a large surface area.

• D The concentration of oxygen in the blood is higher than in the alveoli.

The diagram shows the composition of four samples of air (O2 = oxygen, CO2 = carbon dioxide, N2 = nitrogen).

• A

• B

• C

• D

What makes alveoli suitable as a gas exchange surface?

• A

• B

• C

• D

Which word equation shows anaerobic respiration in yeast?

• A

• B

• C

• D

An experiment is set up as shown. After four hours, the coloured water will

• A have gone down by the same amount in both tubes.

• B be higher in tube 1 than in tube 2.

• C be higher in tube 2 than in tube 1.

• D have gone up by the same amount in both tubes.

The diagram shows an experiment to study respiration in growing barley seeds.The results of this experiment show that respiration

• A produces carbon dioxide.

• B releases energy.

• C requires glucose.

• D uses up oxygen.

An experiment is set up as shown. Flasks 1 and 2 contain lime water. Air is pumped through the flasks.

• A

• B

• C

• D

In the body of a human, which processes consume energy from respiration?

• A

• B

• C

• D

Which substance is produced in both aerobic respiration in humans and anaerobic respiration in yeast?

• A carbon dioxide

• B ethanol

• C lactic acid

• D water

Which substance builds up in a muscle as a result of anaerobic respiration?

• A carbon dioxide

• B ethanol

• C lactic acid

• D oxygen