Describe double fertilization in flowering plants                            (4mks)

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An animal has 6 molars, 2 canines, 4 incisors and 6 premolars in the lower jaw while the upper jaw has 6 molars, 4 premolars, 0 incisors and 2 canines in the upper jaw

(a) What is the significance of absence of incisors in the upper jaw to the feeding of the animal           (2mks)

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(b) Write the correct dental formula for the animal                      (1mk)

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(c) Why do such animals have a longer alimentary canal?                   (2mks)

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Use the photograph shown below to answer questions that follow

(a) Explain the role of prothoracic gland during this phase of metamorphosis  (2mks)

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(b) State the significance of this process to the life of the insect                        (1mk)

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a) Name the chemical form in which the following are transported in the blood            (2mks)

 i) Carbohydrates

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 ii) Carbon (IV) Oxide

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b) Explain why transfusion of blood from a blood group B donor to a recipient with blood group A may be fatal.           (2mks)

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Study the photomicrograph shown below and answer the questions that follow

(a) Name the parasite shown in the photo above                                  (1mk)

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(b) Which organism is the vector of the parasite?                                   (1mk)

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(c) Calculate the magnification used to obtain the image shown above       (3mks)

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A protein has 100 amino acids. Calculate the number of nitrogenous bases in the gene for this protein            (2mks)

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Use the images shown below to answer questions that follow

(a) Why are the structures above said to be homologous structures?                 (1mk)

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(b) Which type of evolution is represented above?                                                         (1mk)

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(c) What is the significance of the type of evolution named in b) to animals?   (1mk)

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How are the following significant to the development of seeds

(a) Seed dormancy                                                            (2mks)

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(b) Seed dispersal                                                              (2mks)

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The illustration shown below is of a common organism

(a) Why is the above organism medically important globally?                         (2mks)

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(b) Name the class to which the organism belongs.                                                         (1mk)

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(c) Give two reasons for your answer in b) above                                                        (2mks)

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Use the illustration shown below to answer the questions that follow

(a) Why is the right kidney slightly pushed higher up compared to the left kidney?   (1mk)

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(b) Explain how gland labelled Z help raise amount of Sodium ions (Na+) in the blood      (2mks)

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