Home > Biology O LevelVariant 2 February/March 2016 Report a question What’s wrong with this question? You cannot submit an empty report. Please add some details. 0% Variant 2 February/March 2016 1. What is not an effect of the hormone adrenaline? increased blood glucose increased pulse rate dilated pupils decreased production of sweat 2. Which hormone maintains the lining of the uterus during pregnancy? progesterone testosterone oestrogen FSH 3. The diagram shows a large food molecule changing into smaller molecules. What is process X? secretion absorption digestion chewing 4. Which row shows the chambers of the heart, from those with the thickest walls to those with the thinnest walls? A B C D 5. Possible effects of drug abuse include 1 addiction, ย ย 2 reduced self-control, ย ย 3 severe withdrawal symptoms. Which effects may occur as a result of drinking too much alcohol? 1, 2 and 3 2 and 3 only 1 only 1 and 2 only 6. The diagram shows a leaf. Use the key to identify the plant to which the leaf belongs. A B D C 7. What is a correct way of naming an organism using the binomial system? Ranunculus sp. Common buttercup Ranunculus acris ranunculus acris 8. Why is aspirin sometimes used as a drug to reduce the risk of coronary heart disease? It reduces pain. It reduces the tendency for blood to clot It reduces blood pressure. It relaxes artery walls. 9. The table shows the conditions in four test-tubes containing equal amounts of starch and salivary amylase. In which test-tube is the starch broken down fastest? C D B A 10. The diagram shows an experiment to investigate the response of a plant stem to gravity. What is a suitable control for this experiment? D A B C 11. What is not a feature of hydrophytes? large air spaces in the tissues leaves rolled up and covered with hairs leaves with stomata on the upper surface roots and xylem reduced 12. What happens when a child is vaccinated against tuberculosis? D C A B 13. The diagram shows five stages in genetic engineering. Which stages involve the formation of sticky ends? 1 and 3 only 2 and 3 only 1, 2 and 3 1 and 2 only 14. The diagram shows a flower. In which structure do seeds develop? C A D B 15. What are alleles? the total number of genes on one chromosome a pair of chromosomes different versions of the same gene two genes side by side on the same chromosome 16. In sexual reproduction in humans, why are sperm cells produced in much greater numbers than egg cells? Sperm cells live for only a short time. Sperm cells are small in size. The chance of one sperm cell reaching an egg is very small. More than one sperm cell fertilises an egg. 17. The diagram shows a section of DNA, with four bases identified on one strand. Which sequence of bases would be on the other strand, starting from the top? TCAG CTGA AGTC GACT 18. The data show the results of an investigation on osmosis using sticks of potato. Which statements explain this change in length? A C B D 19. The diagram shows a palisade mesophyll cell from a green leaf. In which labelled part does photosynthesis occur and where is starch stored? D A C B 20. What helps oxygen to be absorbed rapidly into the blood in the lungs? Alveoli have thin walls and a large surface area. Air breathed in has less oxygen than air breathed out. The concentration of oxygen in the blood is higher than in the alveoli. Alveoli have thick walls and a large surface area. 21. The fovea of the eye has three kinds of cones absorbing light of different colours. Which row is correct? C A D B 22. The diagram shows the inheritance of ABO blood groups. The blood groups of some of the individuals are given. What could be Priyaโs genotype? IOIO IBIO IBIB IAIO 23. A plant with variegated leaves has the starch removed from its leaves by placing it in a dark cupboard for 48 hours. Black paper is then fixed on one leaf as shown and the plant is exposed to light. After 24 hours, which part of the leaf contains starch? D B A C 24. The diagram illustrates changes in air pressure taking place inside the lungs during a complete cycle of breathing. Atmospheric pressure is 101 kPa. At which point on the diagram are the ribs beginning to be lowered? C D B A 25. The diagram shows the sex chromosomes of a woman and of a man. Their genotypes for a recessive sex-linked condition are also shown. What are the chances that their daughter will show the sex-linked condition? 0% 50% 25% 75% 26. A person eats a large bowl of rice. What happens to the amounts of insulin, glucagon and glycogen in their body? C D A B 27. What is not an example of active transport? uptake of ions by root hairs uptake of glucose by villi reabsorption of glucose by kidney tubules absorption of water by root hairs 28. The diagram shows a pyramid of numbers in a food chain. What type of organism is the hawk? tertiary consumer primary consumer producer quaternary consumer 29. What causes the diffusion of oxygen into a plant cell? osmosis movement of molecules photosynthesis active transport 30. By which process is water lost from a leaf? diffusion osmosis photosynthesis active transport 31. The diagram shows part of the alimentary canal and associated organs. Which structures secrete enzymes that digest proteins? T and U W and T U and V V and W 32. The graph shows pH changes in the mouth after eating. Why is it a good idea to brush teeth after eating? Alkaline conditions help bacteria to grow. Acids dissolve tooth enamel. Acidic conditions help bacteria to grow. Alkalis dissolve tooth enamel. 33. The diagram shows the detailed structure of a plant cell. What is organelle X? nucleus chloroplast vacuole mitochondrion 34. The diagram shows organisms feeding on a dead rat and one of the organisms which, in turn, feeds on them. What is needed to complete the food chain? carnivore producer predator consumer 35. The diagram represents the shape of an enzyme molecule. With which substrate would this enzyme most easily form an enzyme-substrate complex? B A D C 36. The lower end of a plant stem is placed in water coloured with red dye. After three hours, the stem is cut as shown in the diagram. Which labelled region is stained red? C B A D 37. Which row shows the effects of deficiencies in nitrate and magnesium ions on plant growth? B D C A 38. Which process is used to transport sucrose from the leaves of a plant to its flowers? osmosis translocation transpiration diffusion 39. The careless use of nitrogenous fertiliser near rivers and lakes can cause eutrophication. This results in the death of fish. What is the direct cause of the death of the fish? The rapid growth of producers uses up all the available nutrients. Decomposers reduce the amount of dissolved oxygen in the water. The sudden increase in the number of bacteria increases the spread of disease. Nitrates are toxic to plants. 40. The diagram shows the structure of a kidney tubule. Where does filtration occur? C A B D Your score is The average score is 0% 0% Restart quiz