EXAMINATIONS COUNCIL OF SWAZILAND in collaboration with UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS Swaziland General Certificate of Secondary Education *493762 9 4 33* BIOLOGY 6884/02 Paper 2 Core October/November 2010 1 hour 15 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a soft pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. Answer all questions. Write your answers in the spaces provided on the question paper. You may use a calculator. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. 1 2 3 4 5 6 7 8 9 Total This document consists of 12 printed pages. DC (SM/SW) 19702/6 [Turn over
1 Sibongile loves playing with her puppy, Spotty, when she comes back from school. Spotty jumps high to touch Sibongile s chest. Sometimes he urinates while wagging his tail. They both run around the yard until Spotty pants with saliva dropping from his tongue. When Spotty sees Sibongile he displays a characteristic of living things called sensitivity. 2 (a) (i) Identify from Spotty s behaviour two other characteristics of living things. 1.... 2....[2] State two ways in which plants show sensitivity. 1.... 2....[2] (b) Fig. 1.1 shows the leaves of four different plants. A B C D Fig. 1.1 the key below to identify the plants A, B, C and D. 1. Leaves divided into smaller leaflets... go to 2 Leaves not divided into smaller leaflets... go to 3 genus 2. Leaflets with jagged (toothed) edges... Leaflets with smooth edges... 3. Leaves with jagged (toothed) edges... Leaves with smooth edges... Rubus hispidus Acacia farnesiana Amelanchier sanguinea Cocculus carolinus A... B... C... D [3] [Total: 7]
2 Fig. 2.1 shows an apparatus used to investigate the action of the enzyme lipase on peanuts that were ground into powder. Equal amounts of water, bile salts and peanut powder were added into test tube E and test tube F. Enzyme lipase was added to test tube E only. Both test tubes were kept at 37 C. 3 lipase bile salts + peanut powder in water at 37 C E (a) Define the term enzyme. Fig. 2.1 F (b) Explain why the bile salts were added. (c) Explain why the temperature of the water had to be maintained at 37 C. (d) State the purpose of test tube F in the experiment.... (e) The pupil added ethanol into each of the test tubes to test for fats. Describe what he would most likely observe in each of the test tubes. test tube E... test tube F...[2] [Total: 9] [Turn over
3 Plants are an important source of food for animals. The leaves play an important role in the making of the food. 4 (a) Name the substance that makes the leaves green.... (b) Name the mineral substance required by plants to form the green pigment.... (c) Describe how light energy from the sun is converted to the chemical energy in starch during photosynthesis....[3] (d) Describe the changes that occur to the starch in maize in the human digestive system to make it ready for absorption into the blood stream....[4] [Total: 9]
4 (a) Menstruation is one of the secondary sexual characteristics in females. 5 Fig. 4.1 shows a female menstrual cycle starting on day 1. 24 23 25 26 27 28 days 1 2 Menstruation 3 4 5 22 6 21 7 20 19 18 17 8 9 10 11 16 15 14 13 12 Fig. 4.1 (i) Name the hormone responsible for the secondary sexual characteristics in females. Mark on Fig. 4.1 with the letter O the day when ovulation is likely to occur. [1] (b) Supposing that the first day of menstruation was on January 17, state the calendar date when sexual intercourse is most likely to lead to pregnancy.... (c) Name two methods by which pregnancy could be prevented. Give an example for each method. method 1... example... method 2... example...[2] [Turn over
6 (d) A person developed a painless ulcer on the genitals which later disappeared on its own. A body rash accompanied with a high body temperature occurred in about six weeks. (i) Name the sexually transmitted infection (STI) the person was most likely to be suffering from. Describe how this stage in the STI promotes the spread of HIV....[2] (e) The terms below are commonly used in reproduction. Match the terms on the left with the correct definition on the right by drawing a line. The first one has been done for you. ovulation the fusion of a sperm and an ovum implantation the release of sperms into the female body fertilization inserting the penis into the vagina sexual intercourse the sinking of a fertilized ovum into the spongy lining of the uterus ejaculation the release of ovum from the ovary [4]
(f) 7 The following, in a random order, are the main stages in the process of birth. 1. amnion breaks 2. placenta expelled from the uterus 3. the baby s head emerges from the vagina 4. contractions of the uterus begin List these stages in the order in which they occur starting with the first to the last one. [Total: 14] [Turn over
5 Water is needed by plants for several chemical processes. 8 (a) Describe the movement of water (i) from the soil into the roots,...[2] from roots to leaves....[2] (b) Most water in plants is lost from the leaves. Describe how each of the following would affect the rate of transpiration. (i) decreasing humidity...[2] increasing light intensity...[2] (c) Lungile, a pupil studying Agriculture, forgot to water the spinach in her garden for five days during which there was no rain. Describe and explain the appearance of the spinach after five days. [Total: 10]
6 Fig. 6.1 shows different blood vessels. 9 G H I Fig. 6.1 (a) (i) Which of the blood vessels, G, H or I is a vein? State one feature that identifies a vein in the diagram. (iii) State the function of an artery. (b) Fig. 6.2 shows some components of blood (not drawn to scale). J K L M Fig. 6.2 (i) Identify a red blood cell from Fig. 6.2. Plasma and white blood cells continuously leak out of the blood capillaries to form tissue fluid. Name two substances required by cells that are found in tissue fluid. 1.... 2....[2] [Total: 6] [Turn over
7 An athlete running a 400 m race experiences change in the breathing rate and muscles start respiring both aerobically and anaerobically. Sometimes the athlete is unable to finish the race due to muscle fatigue. 10 (a) (i) Describe what happens to the athlete s muscles that results in fatigue....[3] State one advantage of aerobic respiration. (iii) Write a word equation for aerobic respiration....[2] (b) Compare the rate and depth of breathing before and immediately after a race. rate. depth...[2] (c) Describe the test for carbon dioxide and state the positive result. [Total: 10]
8 Ayanda was stung on her arm by a wasp. This caused Ayanda to move her arm quickly away from the wasp. 11 (a) (i) Complete the flow chart by putting the following terms in the boxes to show the route of the impulse from the time Ayanda was stung to the time she reacted. effector receptor response stimulus stimulus N central nervous system O [3] Identify and name the neurones at N and O. N... O...[2] (b) The central nervous system in Ayanda s reflex action is represented by the spinal cord. State the parts that represent the following. (i) effector... receptor... (iii) response... (iv) stimulus...[4] [Total: 9] [Turn over
9 Down s syndrome is a condition caused by mutation, which results in variation. 12 (a) Define the term mutation.... (b) State two causes of mutation. 1.... 2. [2] (c) Name the type of variation shown by blood groups in humans.... (d) Commercial crops are often made to yield better produce by genetic engineering. Define genetic engineering. [Total: 6] Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (ECOS) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity.