Biology Y9 HY Page 1 of 12

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1 S E C O N D A R Y S C H O O L - M R I E Ħ E L HALF-YEARLY EXAMINATIONS 2017/2018 YEAR 9 Biology Time: 2 hours Name: Class: Section A: Answer ALL the questions in this section in the space provided. This section carries a total of 55 marks. 1) The following diagram shows a root hair cell. a) i) Name the process by which water is absorbed by the roots. ii) How is the root cell adapted for this process? (1, 1) b) The root hair cell lacks an organelle that is normally found in all plant cells. Explain this statement. Total: 3 marks Biology Y9 HY Page 1 of 12

2 2) The cell is the basic unit of life. All organisms are made up of cells (or in some cases, a single cell). a) Draw and label a typical animal cell. (3) b) Fill in the function of each of the structures found in animal and plant cells (6) Structure Function Nucleus Cell Wall Cell Membrane Cytoplasm Vacuole Chloroplast Total: 9 Marks Biology Y9 HY Page 2 of 12

3 3) Single celled organisms rely on diffusion to get the nutrients they need and to get rid of waste products a) Define the term diffusion. b) The following table shows 4 cubes with different side length: Cube Side Length Surface Area in cm2 Volume in cm3 S.A. : Vol Ratio A 2 24 B C D i) Fill in the above table (you may use your calculator). (4) ii) What is the relationship between size and the surface area to volume ratio? iii) Which cube would have the fastest rate of diffusion? Explain why. (1,1) iv) Human beings need lungs for efficient gaseous exchange. Explain this in terms of surface area to volume ratio. Total: 10 marks Biology Y9 HY Page 3 of 12

4 4) A flower contains the reproductive parts needed for sexual reproduction. a) State whether the diagram above shows a wind pollinated plant or an insect pollinated plant. b) Give 2 reasons for your answers in (a). c) Fill in the missing information about the parts of a flower in the table below (6) Structure Function Sepal May be brightly coloured to attract insects The male part of the flower, made up of an anther attached to a filament Anther Stigma Produces the female sex cells (contained in the ovules) Total: 9 marks Biology Y9 HY Page 4 of 12

5 5) Flowers are responsible for producing seeds, which ensure growth of new plants. a) What is the importance of seed dispersal? b) The diagram below shows the seed of the dandelion plant. i) Name the type of dispersal carried out by such seeds. ii) Explain how the above-mentioned dispersal works. c) The diagram below shows a different seed. i) Name the type of dispersal carried out by such a seed. Give a reason for your answer. d) Dispersal has its own disadvantages. Explain. (1,1) Total: 7 marks Biology Y9 HY Page 5 of 12

6 6) Plants can either be monocotyledons (monocots) or dicotyledons (dicots). a) Fill in the table below to explain the differences between stems, leaves and roots of monocots and dicots. (6) Part Arrangement in Monocots Arrangement in Dicots Stem Leaf Root b) The following diagram shows the structure of a typical plant. i) Mention one function of the stem which you can see in the diagram ii) Mention one function of the stem that is NOT visible in the diagram. c) Name the two main functions of the roots. d) What is the importance of the epidermis layer in the leaf? Total: 11 marks Biology Y9 HY Page 6 of 12

7 7) Some plant cells taken from a leaf of a plant were placed in a strong salt solution for 4 hours, and ended up as shown below. a) Explain what has happened to the cell above. b) Predict, with reasons, what will happen to the cells if they were put in: i) Distilled water; ii) An isotonic solution. Total: 6 marks End of Section A: Total 55 Marks Biology Y9 HY Page 7 of 12

8 Section B: Answer question ONE and ANY OTHER TWO questions on the papers provided. This section carries a total of 45 marks. 1) The following case study concerns the relationship between the lynx and the snowshoe hare between 1895 and The lynx is a type of white cat living in the forests of Canada, while the snowshoe hare is a type of rabbit also living in the same forest. The lynx prey on snowshoe hares. In some areas, hare provide over 70 % of the lynx diet. As a result, the population growth curve of the lynx should show a relationship to that of the hare. The data of this relationship is shown in the table below: Year Hare numbers Lynx numbers a) Plot this data on the graph paper provided (found on the last page page 12). The lynx numbers have already been plotted for you as an example. (4) b) From the above relationship, which animal is the predator? c) Explain why the prey population is always higher than that of the predator. d) Mention two adaptations predators have to help them catch prey successfully. e) What happens to the lynx population when the hare population increases? Why? f) What happens to the hare population when the lynx population increases? Why? g) Later on in the years, a virus attacked the lynx. Write two disadvantages the hare population might have faced. h) We say that a good predator-prey relationship keeps the two populations in balance. What is meant by this? Total: 15 Marks Biology Y9 HY Page 8 of 12

9 2) It is easy to say that a dog is living, and that a rock is not. This is because of specific functions which can be done by living things only. a) Fill in the missing information in the table below (7) Life Process Definition Taking up food needed for growth and energy Growth Getting energy from food The production of offspring from parents Movement Starting to sweat when feeling hot Excretion b) Single celled organisms need to carry all the above processes by themselves. When organisms become more complex, cells start specialising, in order to cater for various specific functions. i) What are specialised cells? ii) What is the advantage of an organism having several different specialised cells? c) Draw and name one specialised cells found in the human body d) How is the cell in iii adapted to its function? e) Sort the following in order of simplest to more complex: Organ, Tissue, Organelle, Cell, System, Organism (3) Total: 15 marks 3) Using relevant biological knowledge, explain why each of the following statements is FALSE: a) All molecules enter a cell by diffusion only. (3) b) In flowering plants, the role of flowers is to perform photosynthesis. (3) c) The rate of diffusion is only affected by temperature. (3) d) Both osmosis and active transport are types of passive transport, while diffusion is not. (3) e) Asexual reproduction produces few individuals in a short time, and leads to a lot of variation (3) Total: 15 marks Biology Y9 HY Page 9 of 12

10 4) John and Mary wanted to investigate the effect of different solute concentrations on the length of potato cuttings. They measured and cut 3 identical cuboids, measuring 5cm x 3cm x 3 cm (L, B and H), and placed them in 3 separate beakers with different salt concentrations, as shown in the table below: Beaker/Cube Original Length in Final Length in Change cm cm A 5 cm 5 cm 0cm B 5 cm 8 cm +3cm C 5 cm 3 cm -3cm a) Define osmosis. b) Why is it important that the potatoes were cut into exact identical sizes? c) Why is a semipermeable membrane important? d) Name two factors that need to be kept constant while performing this experiment. e) The students noticed that one of the potato strips was harder than the others. Which one would you expect this to be? Give a reason for your answer. f) All fresh water amoebae need a contractile vacuole to survive. Explain, using diagrams, this biological statement. (4) g) When a patient is dehydrated (lacks water), saline (a solution containing salts) is given to a patient intravenously as shown below. Suggest why pure water is never given to such patients. (You may use diagrams to better illustrate your reasoning). (3) Total: 15 marks Biology Y9 HY Page 10 of 12

11 5) Pollination is the process by which plants produce seeds. a) Pollination can occur in two ways: self-pollination and cross-pollination. i) Explain the difference between these two types of pollination. ii) Describe one situation when self-pollination is necessary. b) Explain why certain stigmas are feathery. c) A seed may remain dormant for a very long time before germinating. Why is this necessary and advantageous? d) The following show two types of germination: i) Which of the above diagrams shows hypogeal germination? Give a reason for your answer. (1,1) e) A seed needs to be sowed at the right depth in order to ensure successful growth. Explain why. f) Germination depends on three factors. i) Name these three factors (3) ii) Explain the importance of each of the mentioned factors. (3) Total: 15 marks Biology Y9 HY Page 11 of 12

12 Number of Hare Total Lynx and Snowshoe Hare Population Numbers by Year X Number of Lynx X X X X X X X X Years Biology Y9 HY Page 12 of 12