B3.1 Gas exchange questions for IB Biology

44 questions on Gas exchange, written by Augment in the style of IB exam papers. Six of them are below in full, to answer on paper.

  • IB Biology
  • Part of B Form and function
  • SL and HL

Questions by paper and level

SL and HL questions are for students at either level. HL only questions cover what only HL students study.

PaperSL and HLHL onlyAll
Paper 1A14620
Paper 1B415
Paper 211819
Every paper291544

Counted on

Questions to try

Written by Augment in the style of IB exams, not past papers. Answer them on paper, then check each one against its markscheme with a free account.

Question 1 · BIO-00433Paper 1A · 1 mark

Two cube-shaped models of organisms have sides of 1 mm and 4 mm. Which statement about the 4 mm cube, compared with the 1 mm cube, is correct?

  1. A

    Its surface area-to-volume ratio is four times greater and its centre is closer to the surface

  2. B

    Its surface area increases by a greater factor than its volume

  3. C

    Its surface area-to-volume ratio is one quarter as large and its centre is four times further from the surface

  4. D

    Its surface area-to-volume ratio is unchanged because surface area and volume both increase

The answer and whyCheck this one with a free account
Question 2 · BIO-00453Paper 1B · 9 marks

Students compared the stomatal density of the upper and lower surfaces of leaves from three species: ivy (Hedera helix), a climbing plant of shady walls; maize (Zea mays), a grass with upright leaves; and water lily (Nymphaea alba), whose leaves float on the surface of a pond. Clear nail varnish was painted on each surface, allowed to dry, peeled off with clear tape and mounted on a slide. Stomata were counted in 10 fields of view at ×400 magnification on casts from five leaves of each species. The field of view had a diameter of 0.45 mm.

Species

Leaf surface

Mean number of stomata per field of view

Standard deviation

ivy

upper

0.0

0.0

ivy

lower

28.4

3.6

maize

upper

9.8

2.1

maize

lower

13.6

2.5

water lily

upper

62.3

6.8

water lily

lower

0.0

0.0

  1. (a)

    State the dependent variable in this investigation.

    1 mark

  2. (b)

    Calculate the stomatal density of the lower surface of ivy leaves. Show your working.

    2 marks

  3. (c)

    Outline why stomata were counted in ten fields of view on casts from five different leaves.

    2 marks

  4. (d)

    Suggest one source of error when counting stomata on a leaf cast.

    1 mark

  5. (e)

    Explain the distribution of stomata on the leaves of water lily and ivy.

    3 marks

The markschemeCheck this one with a free account
Question 3 · BIO-00035Paper 2 · 15 marks

Organisms are adapted to the physical environments in which they live.

  1. (a)

    Compare and contrast water and air as habitats for animals, with reference to the black-throated loon (Gavia arctica) and the ringed seal (Pusa hispida).

    7 marks

  2. (b)

    Describe the properties of gas-exchange surfaces.

    4 marks

  3. (c)

    Outline how the hydrophobic properties of lipids are used by organisms.

    4 marks

The markschemeCheck this one with a free account
Question 4 · BIO-00434Paper 1A · 1 mark

Why must gas-exchange surfaces be kept moist?

  1. A

    Oxygen and carbon dioxide must dissolve in water before they can diffuse across the cell membranes

  2. B

    A layer of water makes the exchange surface thinner

  3. C

    Water increases the surface area available for diffusion

  4. D

    Water actively transports oxygen across the exchange surface

The answer and whyCheck this one with a free account
Question 5 · BIO-00454Paper 1B · 9 marks

A leafy shoot of geranium (Pelargonium sp.) was cut under water and fitted into a bubble potometer. A fan was placed beside the shoot and its speed adjusted to give wind speeds measured with an anemometer at the leaves. After 10 minutes at each wind speed, the distance moved by an air bubble along the capillary tube in 5 minutes was recorded. Three readings were taken at each wind speed. The capillary tube had an internal cross-sectional area of 0.79 mm2.

Wind speed / m s-1

Distance moved in 5 min, reading 1 / mm

Reading 2 / mm

Reading 3 / mm

Mean distance / mm

0

12

14

13

13.0

1

25

22

26

24.3

2

34

38

35

X

3

41

44

40

41.7

4

45

43

47

45.0

  1. (a)

    Calculate the mean distance, X, for a wind speed of 2 m s-1.

    1 mark

  2. (b)

    Calculate the rate of water uptake by the shoot at a wind speed of 4 m s-1. Give the units.

    2 marks

  3. (c)

    Describe the effect of wind speed on the distance moved by the bubble.

    2 marks

  4. (d)

    Explain the effect of wind speed on the rate of transpiration.

    3 marks

  5. (e)

    Suggest why the shoot was cut under water before it was fitted into the potometer.

    1 mark

The markschemeCheck this one with a free account
Question 6 · BIO-00143Paper 2 · HL only · 15 marks

Animals use energy released by cell respiration to move.

  1. (a)

    Explain how ATP is produced by chemiosmosis in mitochondria.

    7 marks

  2. (b)

    Describe how antagonistic muscles move the ribcage during ventilation of the lungs.

    4 marks

  3. (c)

    Suggest reasons why some animals undertake long-distance migrations despite the large amounts of energy used.

    4 marks

The markschemeCheck this one with a free account

Practice all 44 in Augment

Free with an account. Every question has its markscheme, and Augment keeps the ones you got wrong so you can come back to them.

Start freeLog in

The notes on B3.1 Gas exchange

More questions in Form and function

  1. B1.1Carbohydrates and lipids
  2. B1.2Proteins
  3. B2.1Membranes and membrane transport
  4. B2.2Organelles and compartmentalisation
  5. B2.3Cell specialisation
  6. B3.1Gas exchangeThis page
  7. B3.2Transport
  8. B3.3Muscle and motilityHL only
  9. B4.1Adaptation to environment
  10. B4.2Ecological niches

Check your answers in Augment

A free account opens all 44 questions on Gas exchange with their markschemes, and keeps a record of what you have marked.

Start free