BIOLOGY - ORDINARY LEVEL

Transcription

1 WARNING: This Question Paper MUST be returned with your answer book(s) at the end of the Examination: otherwise marks will be lost. STUDENT NAME SCHOOL L.37 For Examiner s use only Sect. Q. Mark Sect. A Sect. B Sect. C TEACHER TOTAL PRE-LEAVING CERTIFICATE EXAMINATION, 2010 BIOLOGY - ORDINARY LEVEL TIME : 3 HOURS Section A Answer any five questions from this section. Each question carries 20 marks. Write your answers in the spaces provided on this examination paper. Section B Answer any two questions from this section. Each question carries 30 marks. Write your answers in the spaces provided on this examination paper. Section C Answer any four questions from this section. Each question carries 60 marks. Write your answers in the answer book. It is recommended that you should spend not more than 30 minutes on Section A and 30 minutes on Section B, leaving 120 minutes for Section C. You must return this examination paper with your answer book at the end of the examination L.37 1/12 Page 1 of 12 [OVER]

2 Section A Answer any five questions. Write your answers in the spaces provided. 1. Answer any four of the following parts: (a) Which type of blood vessel in humans contains valves? Antibiotics can be used to treat which types of disease-causing organisms? (c) To protect a farm animal from a plant toxin, a gene for resistance to the toxin was transferred to the farm animal. What term describes this process? (d) Name the process in the body which involves maintaining a constant internal environment. (e) What is the role of antigens in the body s defence against disease? 2. Select the correct description from the following list and write it in Column B to match the term in Column A. The first one has been completed as an example: educated guess, energy release, movement of molecules, comparison, groups of cells Column A Column B Hypothesis educated guess Organisation Respiration Diffusion Control 2010 L.37 2/12 Page 2 of 12

3 3. (a) Complete the following table in relation to food tests: Test for Reagent Colour if present Benedict s solution Red Starch Blue/black Protein Biuret reagent Name a fat soluble vitamin. (c) Give a function of the vitamin you have named in. (d) Three chemical elements form fat molecules: Carbon (C), Hydrogen (H) and which other element? (e) Give a function for each of these polysaccharides in plants: (i) Starch (ii) Cellulose 4. Indicate whether the following are true (T) or false (F) by drawing a circle around T or F in each case. Example: Blinking is an example of a reflex action T F The central nervous system is made up of the brain and the spinal cord. T F Sensory neurons carry impulses to the sense organs. T F The cerebellum is the largest part of the human brain. T F Impulses can travel along neurons in either direction. T F Synapses are small gaps between neurons. T F 2010 L.37 3/12 Page 3 of 12 [OVER]

4 5. (a) List three components of an animal cell which can be seen using a light microscope What is meant by an anabolic reaction? Give one example of an anabolic reaction. Anabolic reaction Example (c) What term is used to describe the sum of all the chemical reactions in a cell? (d) Cells use enzymes to carry out various functions. What is an enzyme? (e) Enzyme reactions are reversible. Explain the underlined term. 6. Name the structure in the mammalian eye that is referred to in each of the following statements: (a) This layer contains a lot of dark pigment to minimise light scattering within the eye and is rich in blood vessels. When this contracts the lens changes shape. (c) It carries impulses to the brain. (d) It controls the amount of light that reaches the retina. (e) It is made of tough, collagen fibres and helps maintain the shape of the eyeball L.37 4/12 Page 4 of 12

5 Section B Answer any two questions. Write your answers in the spaces provided. Part (a) carries 6 marks and part carries 24 marks for all questions in this section. 7. (a) (i) Enzymes are proteins. Name three chemical elements present in enzymes (ii) Where in a cell are enzymes made? Answer the following questions in relation to an investigation you carried out to show the effect of ph on the rate of enzyme activity. (i) (ii) Name the enzyme you used. Name the substrate you used. (iii) Draw a labelled diagram of the apparatus you used. (iv) (v) (vi) How did you measure the rate of reaction of the enzyme? What factor did you keep constant during your investigation? How did you ensure this factor remained constant? 2010 L.37 5/12 Page 5 of 12 [OVER]

6 8. (a) Explain the following terms used in ecology: (i) Flora (ii) Fauna (i) From an ecosystem (or habitat) you have studied name two methods used to collect animals (ii) In carrying out a quantitative survey describe how you used a transect and a quadrat. Transect: Quadrat: (iii) Suggest two reasons why your survey may not produce an accurate description of life in the selected ecosystem (or habitat) L.37 6/12 Page 6 of 12

7 9. (a) (i) What is meant by dormancy in seeds? (ii) Give an advantage of dormancy. Answer the following questions in relation to practical work you carried out to investigate the factors needed for seed germination. (i) Draw a labelled diagram of the apparatus you used. (ii) Explain how you carried out your investigation. (iii) Why was a control apparatus necessary? (iv) Why were a number of seeds used in each apparatus rather than a single seed? 2010 L.37 7/12 Page 7 of 12 [OVER]

8 Section C Answer any four questions. Write your answers in the answer book. 10. (a) (i) The diagram shows a cross section of an alveolus. Which structure in the following list is represented by each of the letters A, B and C: capillary, bronchiole, red blood cell? (ii) Name one animal tissue shown in the diagram. (9) (i) The alveolus is a structure in the lung used for gaseous exchange. Explain what is meant by gaseous exchange in this example. (ii) List three ways in which the alveolus is adapted to its function of gaseous exchange. (iii) Name the major blood vessel which carries blood (a) into the lungs, out of the lungs. (iv) Name the organ in the body that controls the rate of breathing. (27) (c) (i) Outline the events which occur in the body when a single breath is inhaled. (ii) The results of an investigation into the Student Breathing rate (breaths per minute) effect of exercise on breathing rate are Before During After shown in the table. exercise exercise exercise 1. Explain why breathing rate increases during exercise. A B Data in the table indicate that one of the students may be showing symptoms of a breathing disorder. Which student do you think this is? (iii) Name a breathing disorder in humans. State a possible cause of this disorder and suggest a method of treatment. (24) 11. (a) Define the following terms: ecology, ecosystem, biosphere. (9) (i) One of the negative impacts of humans on the ecosystem is pollution. Explain what is meant by pollution. (ii) Give the effect of one pollutant from any of the following areas: domestic, agricultural or industrial. (iii) Explain what is meant by the term conservation. (iv) Give one example of waste management in either agriculture, fisheries or forestry. (v) Name two problems associated with waste disposal. (vi) Suggest three ways to minimise waste. (27) (c) (i) The life of an organism is affected by environmental factors, biotic and abiotic. Explain the underlined terms. (ii) Ecosystems are unable to function unless there is a constant input of energy from an external source. What is the primary source of energy on our planet? (iii) Name a habitat (ecosystem) you have studied. (iv) Give a simple food chain, containing three organisms, from this habitat. (v) To which trophic level does each of your food chain organisms belong? (24) 2010 L.37 8/12 Page 8 of 12

9 12. (a) In certain breeds of hens the gene determining feather colour has two alleles that show a lack of dominance. The allele B when homozygous produces black feathers; the allele b when homozygous produces white feathers. The heterozygous condition produces grey feather colour. (i) Explain the three underlined terms. (9) (i) Draw a genetic diagram to show the results of a cross between a grey hen and a white cockerel. Include the following in your diagram: parental phenotypes, parental genotypes, gametes, offspring genotypes, offspring phenotypes and phenotypic ratio. (ii) A breeder wishes to obtain hens which are all grey in colour. Suggest a cross which would produce such a population. (27) (c) It is now known that DNA makes up the hereditary material in cells. (i) What do the letters DNA stand for? (ii) Where in the cell is DNA most widely found? (iii) Name or give the letters that represent the four bases which form the DNA molecule and name (or state the letter of) a base found in RNA which does not appear in DNA. (iv) State one difference (other than bases present) between the structure of DNA and RNA. (v) Name the technique used to identify the presence or absence of changed genes. (24) 13. (a) (i) Name the pores on the surface of the leaf which allow entry and exit of gases. Give the name of the cells which control these pores. (ii) Name the pigment in a chloroplast which traps sunlight energy. (9) (i) Give one use in plants for each of the products of photosynthesis. (ii) Give one reason why photosynthesis is important to other living organisms. (iii) Outline the main events in the process of photosynthesis. Include at least six of the following words in your account: carbon dioxide, chlorophyll, electrons, glucose, light, oxygen, protons, water. (27) (c) A student set up an experiment to investigate how various environmental factors affect the rate of photosynthesis using the apparatus shown. (i) Name a plant which would be suitable for the investigation and state how the rate of photosynthesis is measured. (ii) Name one factor which the student could have varied and suggest how they may have varied the factor you have named. (iii) Suggest any two pieces of apparatus, other than those shown in the diagram, which the student would have needed to carry out the investigation. (iv) Give a reason why each of the two pieces of apparatus you have suggested is used. (24) 2010 L.37 9/12 Page 9 of 12 [OVER]

10 14. Answer any two of (a), and (c). (30, 30) (a) The diagram shows the human female reproductive system. (i) Name the parts A, B, C, D and E. (ii) In which of the labelled parts does each of the following events occur: ovulation, insemination, fertilisation, implantation? (iii) In which of the labelled parts does meiosis occur? (iv) Reproduction involves gametes and fertilisation. Explain the underlined terms. (v) Explain what is meant by infertility in relation to human reproduction and give one possible cause of female infertility. (i) The diagram above shows an important reproductive structure from a flowering plant. Name this part and state whether it is male or female. (ii) Identify the structures labelled A, B, C and D. (iii) After pollination and fertilisation, reproduction in flowering plants leads to seed formation and seed dispersal. Explain the underlined terms. (iv) Give two advantages of seed dispersal. (v) What is meant by the term vegetative propagation in plants? (c) (i) Nutrition in humans involves ingestion, digestion, absorption and egestion. Explain the underlined terms. (ii) Outline the role of teeth in the human digestive system by mentioning all four types of tooth and their functions. (iii) Give the dental formula for an adult human L.37 10/12 Page 10 of 12

11 15. Answer any two of (a), and (c). (30, 30) (a) (i) Give two differences between a monocotyledonous (monocot) leaf and a dicotyledonous (dicot) leaf. (ii) Draw a diagram of the structure of a leaf in section and label the following parts: upper epidermis, lower epidermis, palisade mesophyll, spongy mesophyll. Label two other parts on the diagram you have drawn. (iii) What is the process by which water enters the root? (iv) Name the tissue which transports water to the leaf. (v) State the process by which water vapour passes out of the leaf. (vi) Name one factor which can affect the rate of the process you named in part (v). (i) Fungi exist in both saprophytic and parasitic forms. Explain the underlined terms. (ii) Describe, using a labelled diagram, or otherwise, the structure of Rhizopus. (iii) What is the function of rhizoids? (iv) Fungi are of economic importance to humans. Give two examples of fungi which are beneficial and outline their benefits in each case. (c) (i) To which kingdom does Amoeba belong? (ii) Draw a labelled diagram to show the structure of Amoeba. (iii) Name one structure in a plant cell which would not be found in an Amoeba. (iv) Water enters Amoeba by osmosis. Define osmosis. (v) Name the structure in Amoeba which plays a role in the removal of excess water. (vi) Nutrition in Amoeba is heterotrophic. Explain the underlined term L.37 11/12 Page 11 of 12 [OVER]

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