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MITOSIS AND MEIOSIS 1. A structure found during animal cell mitosis that is not found during plant mitosis is A cell plate C chiasma B centriole D spindle 2. Figure shows a stage during mitosis in a plant cell. Which of the statements about the cell in the figure is not true? A The cell produces diploid daughter cells B The cell is at anaphase C The cell is found at the apical meristem D The cell has eight chromosomes at interphase 3. In which of the following processes does mitosis take place? I The division of meristematic cells in the stem apex of flowering plants II The formation of pollen grains in the stamen III The production of erythrocytes in the bone marrow IV The reproduction of flatworms by regeneration A I, II and III only B I, III and IV only C II, III and IV only D I, II, III and IV only 4. The correct order of mitosis is represented by A prophase, anaphase, metaphase, B anaphase, telophase, anaphase, C prophase, metaphase, anaphase, D anaphase, metaphase, prophase, telophase metaphase telophase teophase 5. The diagram shows the cytokinesis that occurs in a plant cell. The structure labeled X is A cell membrane B cell wall C D tonoplast cell plate Puteri@acs2010 1. Figure 1 shows phase X and phase Y in the cell cycle of an organism. Phase X consists of three sub phases, P, Q and R Phase Y involves two processes U and V (a) (i) Name process U ________________________________________________________________________ [ 1 mark ] (ii) State two roles of process U in an organism ___________________________________________________________________ ____________________________________________________________________ [ 2 marks ] (b) Figure 2.2 shows the various stages in process U Figure 2.2 (i) Based on Figure 2.2 complete the correct sequence of stages in process U Stage IV Stage ____ Stage ____ Stage ____ [ 1 mark ] Puteri@acs2010 (ii) Name the stages in process U Stage I II III IV Name of stage [ 1 mark ] (c) (i) Name phase X in Figure 2 ______________________________________________________________ [ 1 mark ] (ii) Describe what happens in the cell during phase X ____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ [ 2 marks ] (d) A technique which involves the cell cycle shown in Figure 2 could be used in farming to produce complete new organism. (i) Name the technique used to produce new plants in large quantities. _____________________________________________________________________ [ 1 mark ] (ii) By using one suitable part of the plant, explain the technique used in (d)(i) ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ ________________________________________________________________________ [ 4 marks ] Puteri@acs2010 Answer: 1. B 2.D 3,B 4C 5D Answers: 1(a) (i) Mitosis (i) 1. The process is important in the growth of animals and plants 2.The process is important as it replaces worn out and dead cell in organisms. (b) (i) II III (ii) Telophase (c) I Metaphase Anaphase (i) Interphase New organelles are synthesized The amount of DNA doubled Chromosomes are replicated Proteins are synthesized Energy stores (ATPs) are increased. Prophase Any 2 (d) (i) Tissue culture/cloning (ii) shoot/root/lateral buds or Meristem tissue Shoot/root/lateral buds/tissues is washed and treated with sterilizing agent Tissue is cultured in sterile nutrient medium, suitable temperature Cells divide by mitosis to form callus Callus differentiates to form root and shoot. Essay 1. (a) Amoebae are tiny, unicellular organisms in the Prostista kingdom that can only be seen under a microscope. Explain why the offspring of amoebae are considered clones. [ 4 marks ] (b) In Malaysia, good quality oil palms are produced by cloning. What are the advantages and disadvantages of this technique? [ 6 marks ] (c) In horticulture, orchids are commercially produced and exported. Discuss how you can produce a cloned orchid plant. [ 10 marks ] Answer (a) Clones are cells descended from, and are genetically identical to a single common parent cell Amoebae reproduce by mitotic division of its nucleus Its chromosomes replicate before they separate into two equal portions This is followed by cytokinesis where the cell divides into two Therefore each daughter amoeba is a clone as it is genetically identical to each other and to its parent cell. (b) Special clones can be developed to survive in difficult natural environment But this may upset the balance of nature through the release of genetically altered plant species Cloning is a new and fast way to combat pest epidemics Puteri@acs2010 But as clones are genetically identical, they share the same weaknesses to a disease or a change in climate may wipe out the whole population Significant increase in palm oil production, but overproduction may cause market instability and a fall in price (c) Remove an explant, from a parent orchid plant and cut it into small pieces Sterilize the pieces of tissues with dilute sodium hypochlorite solution Place each sterile tissue into a growth medium The tissue cells are left to divide by mitosis to produce a mass of loosely arranged and undifferentiated cells called callus The callus is then stimulated with shoot stimulating hormone to form multiple shoots Separate the shoots in nutrient medium with root stimulating hormone to encourage rooting Once the roots grow, the plantlets are planted in sterile compost to grow. Puteri@acs2010