Cambridge IGCSE Biology (9-1) 0970 — 2020 May/June Paper 2 · Variant 1

1 The diagram shows what happened in an experiment with plant seedlings. start next day light light Which characteristic of living things made the seedlings grow towards the light? A excretion B nutrition C respiration D sensitivity

Mark scheme: D

More questions on Coordination and response

2 A rat has the scientific name Rattus rattus. What do the two parts of this name refer to? A genus and species B kingdom and genus C kingdom and species D variety and genus

Mark scheme: A

More questions on Concept and uses of classification systems

3 The diagram shows two guard cells. Which label shows the cell wall? B A C D

Mark scheme: D

More questions on Cell structure

4 The diagrams show different levels of organisation in a plant. (Not drawn to scale.) 1 2 3 4 Which sequence shows the levels of organisation in order from smallest to largest? A 4 → 2 → 3 → 1 B 4 → 3 → 1 → 2 C 3 → 4 → 2 → 1 D 3 → 2 → 1 → 4

Mark scheme: A

More questions on Cell structure

5 Which diagram shows the appearance of a plant cell several minutes after it has been placed in a concentrated solution of sugar? A B C D

Mark scheme: A

More questions on Osmosis

6 Plant cells are placed in a solution with a higher water potential than the plant cell contents. What will happen? direction of volume of water movement vacuole A enters cells decreases B enters cells increases C leaves cells decreases D leaves cells increases

Mark scheme: B

More questions on Osmosis

7 The diagram shows a section of DNA, with four bases identified on one strand. G A C T Which sequence of bases would be on the other strand, starting from the top? A AGTC B CTGA C GACT D TCAG

Mark scheme: B

More questions on Chromosomes, genes and proteins

8 Which food-testing solution shows a positive result when it turns from blue to purple? A Benedict’s solution B biuret solution C ethanol D iodine solution

Mark scheme: B

More questions on Biological molecules

9 What is the definition of an enzyme? A a carbohydrate that acts as a catalyst B a DNA molecule that acts as a catalyst C a fat that acts as a catalyst D a protein that acts as a catalyst

Mark scheme: D

More questions on Enzymes

10 An experiment is set up to investigate gas exchange in aquatic plants. hydrogencarbonate indicator solution light aquatic plant The hydrogencarbonate indicator solution is orange at the start. Which colour is it after three hours? A blue-black B orange C purple D yellow

Mark scheme: C

More questions on Photosynthesis

11 The diagram shows how the rate of photosynthesis varies with light intensity. The four curves show different conditions of temperature and carbon dioxide concentration. 30°C, 0.2% CO, 20°C, 0.2% CO, rate of photosynthesis 30°C, 0.1% CO, P 20°C, 0.1% CO, light intensity What limits the rate of photosynthesis at point P? light intensity carbon dioxide temperature concentration key J/ = yes X =no

Mark scheme: C

More questions on Photosynthesis

12 Four test-tubes are set up as shown. Which test-tube contains the least carbon dioxide after one hour? A B C D black water polythene to keep aquatic out light animal light light light aquatic plant

Mark scheme: C

More questions on Photosynthesis

13 The activity of amylase is measured in four parts of the alimentary canal. Which two parts have the most amylase activity? A colon and duodenum B colon and stomach C mouth and duodenum D stomach and mouth

Mark scheme: C

More questions on Chemical digestion

14 Biological washing powder can be used to remove stains on clothing. Which enzymes will remove stains caused by starch, fat and protein? amylase v x x key / = removes stain X = does not remove stain x « & Kx 4 Q 44

Mark scheme: B

More questions on Enzymes

15 The graph shows the rate of uptake of magnesium ions by two similar plants, X and Y. The roots of each plant were placed in a range of solutions. Each solution contained a different concentration of magnesium ions. All other conditions were kept constant. plant X rate of uptake of ions plant Y concentration of magnesium ions in external solution What is a possible explanation for the difference in the results for the two plants? A Plant Y has fewer protein molecules for magnesium ion transport in its cell membranes. B Plant Y has a higher rate of respiration. C Plant Y has more root hair cells. D The root hair cells in plant Y have a lower water potential.

Mark scheme: A

More questions on Active transport

16 What will increase the rate of transpiration in a plant? A an increase in the humidity of the atmosphere surrounding the leaf B an increase in the surface area of the cell surfaces inside the leaf C a decrease in the number of stomata present on the surface of the leaf D a decrease in the temperature of the atmosphere surrounding the leaf

Mark scheme: B

More questions on Transpiration

17 Which pathway is taken by blood in a fish? A gills → heart → body → gills B body → gills → heart → body C heart → gills → body → heart D heart → body → gills → body

Mark scheme: C

More questions on Circulatory systems

18 The diagram shows a section through the heart and its blood vessels. X Which row gives the vessel name and the direction of blood flow in vessel X? vessel name direction of blood flow A aorta towards the lungs B pulmonary artery towards the lungs C pulmonary artery away from the lungs D vena cava away from the lungs

Mark scheme: B

More questions on Heart

19 When a pathogen enters the blood, the immune system uses different mechanisms to destroy the pathogen. The diagram shows one of these mechanisms. X Y pathogen Which row describes the structures involved? structure X X is made by structure Y A antigen lymphocytes antibody B antigen phagocytes antibody C antibody lymphocytes antigen D antibody phagocytes antigen

Mark scheme: C

More questions on Diseases and immunity

20 What is the approximate percentage of oxygen contained in the air breathed out of the lungs? A 0% B 4% C 16% D 20%

Mark scheme: C

More questions on Gas exchange in humans

21 The diagram shows an experiment to investigate the respiration of yeast. Oil prevents oxygen entering the glucose and yeast suspension. delivery tube thin layer of oil bubble of gas glucose and yeast limewater suspension If no oxygen is present in the glucose and yeast suspension, what will occur? A Ethanol will be produced and the limewater will stay clear. B Ethanol will be produced and the limewater will go cloudy. C Lactic acid will be produced and the limewater will stay clear. D Lactic acid will be produced and the limewater will go cloudy.

Mark scheme: B

More questions on Anaerobic respiration

22 Which row correctly completes the balanced equation for aerobic respiration? X + 6O2 → 6CO2 + Y X Y A 6C6H12O6 H2O B C6H12O6 6H2O C 6H2O C6H12O6 D C6H10O6 6H2O

Mark scheme: B

More questions on Aerobic respiration

23 In healthy people, which substance is completely reabsorbed into the blood from the kidney tubules? A glucose B salts C urea D water

Mark scheme: A

More questions on Excretion in humans

24 The diagram shows a synapse. W nerve ending of neurone 1 Y X Z membrane of neurone 2 What are the labelled parts? W X Y Z A synaptic cleft neurotransmitter vesicle receptor B synaptic cleft receptor vesicle neurotransmitter C vesicle neurotransmitter synaptic cleft receptor D vesicle receptor synaptic cleft neurotransmitter

Mark scheme: C

More questions on Coordination and response

25 Which row shows the actions needed for the eye to focus on a distant object? ciliary suspensory lens becomes muscles ligaments A contract slacken thicker B relax slacken thicker C contract tighten thinner D relax tighten thinner

Mark scheme: D

More questions on Sense organs

26 The liver and the pancreas work together to control the concentration of glucose in the blood. Which statement is correct? A The liver converts the small molecule glucose to the large molecule glucagon. B The liver releases the hormone insulin when blood glucose levels are too high. C The pancreas does not respond to an increase in blood glucose levels. D The pancreas responds to a fall in blood glucose by increasing the release of the hormone glucagon.

Mark scheme: D

More questions on Hormones

27 The statements are about the use of antibiotics. 1 using an antibiotic to prevent infection 2 using an antibiotic known to kill the bacteria causing an infection 3 using an antibiotic only when essential 4 using an antibiotic to treat a viral infection Which practices will increase the chance of the development of antibiotic resistance in bacteria? A 1, 2, 3 and 4 B 1 and 4 only C 2 and 3 only D 2 and 4 only

Mark scheme: B

More questions on Drugs

28 Which description of cross-pollination is correct? A the transfer of pollen grains from the anther of one plant to the stigma on a different plant B the transfer of pollen grains from the anther to the stigma on the same plant C the transfer of pollen grains from the stigma of one plant to the anther on a different plant D the transfer of pollen grains from the stigma to the anther on the same plant

Mark scheme: A

More questions on Sexual reproduction in plants

29 The diagram shows a sperm cell. Which part contains enzymes that digest the jelly coat of an egg cell? A B C D

Mark scheme: D

More questions on Sexual reproduction in humans

30 Which cell contains a haploid nucleus? A neurone B sperm cell C skin cell D red blood cell

Mark scheme: B

More questions on Meiosis

31 The diagram shows the chromosomes of four daughter cells produced by meiosis. Which parent cell produced these cells? A B C D

Mark scheme: B

More questions on Meiosis

32 When damaged tissues are repaired cells undergo division by A meiosis to produce genetically identical cells. B meiosis to produce genetically different cells. C mitosis to produce genetically identical cells. D mitosis to produce genetically different cells.

Mark scheme: C

More questions on Mitosis

33 The graph shows the masses of two different types of tomato. type 1 type 2 number of tomatoes 0 20 40 60 80 100 120 140 160 180 200 220 240 mass / g What can be concluded from the graph? A Genes do not affect the mass of tomatoes. B Type 1 tomatoes show continuous variation. C Type 2 tomatoes are sometimes smaller than type 1 tomatoes. D Type 2 tomatoes show discontinuous variation.

Mark scheme: B

More questions on Variation

34 Which adaptation may be present in a xerophyte? A leaves with small surface area and large numbers of stomata B little or no xylem tissue and leaves with large surface area C stomatal hairs and rolled leaves D thin or no cuticle and deep roots

Mark scheme: C

More questions on Adaptive features

35 The diagram shows a food chain in a rock pool. seaweed → whelks → crabs → seagulls What will happen if the number of secondary consumers increases? There will be A fewer crabs. B fewer seagulls. C fewer whelks. D less seaweed.

Mark scheme: C

More questions on Food chains and food webs

36 What is defined as ‘all of the populations of different species in an ecosystem’? A community B environment C habitat D trophic level

Mark scheme: A

More questions on Populations

37 What is the role of anaerobic respiration in bread-making? A to produce alcohol to flavour the bread B to produce gas to make the bread rise C to release enough energy to bake the bread D to release enough lactic acid to kill the yeast

Mark scheme: B

More questions on Biotechnology

38 A crop plant has been genetically modified to make it resistant to herbicides. Which is a possible disadvantage of introducing this new crop plant? A Loss of weeds reduces competition. B Some weeds might become resistant to the herbicide. C The crop plant is unharmed and produces a higher yield. D The new gene will appear in new generations of the crop.

Mark scheme: B

More questions on Genetic modification

39 Which process in the nitrogen cycle is involved in the breakdown of amino acids in living organisms? A deamination B decomposition C denitrification D digestion

Mark scheme: A

More questions on Nutrient cycles

40 When a river is polluted by fertiliser, the following processes may occur. 1 increased aerobic respiration of decomposers 2 increased growth of producers 3 decreased oxygen concentration in the water What is the correct sequence for these processes? A 1 → 2 → 3 B 1 → 3 → 2 C 2 → 1 → 3 D 2 → 3 → 1

Mark scheme: C

More questions on Pollution