SECTION A (40 Marks)

Answer all questions in this section in the spaces provided.

1. In human beings, a downward pointed frontal hairline (“windows peak”) is a heritable trait. A person with windows peak always has at least one parent who has this trait; where as persons with frontal hairline may occur in families in which one or even both parents have windows peak. Using W and w to symbolize genes for this trait

(a) Determine the F1 generation if a homozygous windows peak male parent is married to a homozygous frontal hairlined female parent                                                                                   (4mks)

(b) State two causes of variations                                                                                                          (1mk)

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   c) Name two sex linked genetic disorders affecting human females and males                    (2mks)

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   (d) What is genome                                                                                                                                        

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2. The diagram below shows an organism obtained from an aquatic ecosystem

(a) State the kingdom in which the organism belongs.                                  (1mk)

            ………………………………………………………………………………………………

(b) Name the parts labeled                                                                                                     (1mk)

            B                                                                                                                    

            ………………………………………………………………………………………………

                 Y                                                                                                                            (1mk)                                                                          

            ………………………………………………………………………………………………

(c) State the functions of the following parts

             A                                                                                                                                (1mk)

………………………………………………………………………………………………………………………………………………………………………………………………

 X                                                                                                                                 (1mk)

……………………………………………………………………………………………………………………………………………………………………………………………

Z                                                                                                                                  (1mk)

……………………………………………………………………………………………

(d)Explain briefly why the organism is described as eukaryotic                                           (2mk)

………………………………………………………………………………………………………………………………………………………………………………………………………………

3a) The diagram below shows some of the features of a synovial joint. Study the diagram carefully and answer the questions that follow.

(a)  Name the type of synovial joint.                                                                     (1 mark)

………………………………………………………………………………………………

(b)  Name the parts labeled J,  and L                                                                      (2 marks)

J …………………………………………………………………………………………

            L ………………………………………………………………………………………..

(c)  State two roles of the part labeled L.                                                              (2 marks)

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………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

(d) Suggest one advantage of this type of joint.                                                   (1 mark)

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b) State how the following tissues are adapted to provide mechanical support in plants (2mks)     

i) Parenchyma

……………………………………………………………………………………………   

ii) Collenchyma

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4. A student set up an experiment using soaked and dry seeds as shown below

a)   State the objective of this experiment                                                                   (1mk)

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b)   State the observations made in each of the flask after 24 hours                           (2mks)

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c)   Account for the observation made in (b) above                                                   (2mks)

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d)   Suggest why vacuum flasks were used in this experiment                                   (1mk)

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e)   What alteration would you make in the set-up to make the results more reliable (1mk)

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f)   Why should the seeds be washed with antiseptic/10% formalin?                        (1mk)

……………………………………………………………………………………………………

5 a) Explain how the following meristematic tissues contribute to growth of higher plants

i) Vascular cambium                                                                                                   (2mks)

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ii) Cork Cambium                                                                                                                   (2mks)

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b) The diagram below shows a life cycle of a cockroach

a) Name the hormone that would be at high concentration during.

(i)   First week (1mk)

………………………………………………………………………………………………

(ii) Second week                                                                                                         (1mk)

            ………………………………………………………………………………………………

b) Name the structure that produces hormone in a (ii) above                                                (1mk)              

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c) Name the series of stages through which the nymph undergoes to reach adult stage        (1mks)

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SECTION B (40 Marks) Kapsabet Boys 2022

Answer question 6 (Compulsory) and either question 7 or 8 in the spaces provided.

6. The menstrual cycle is a sequence of events repeated monthly in the female production system. The table below shows the concentration of oestrogen and progesterone hormones and body temperatures of female against time.

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Time in daysOestrogen mg/100cm of bloodProgesterone mg/100cm3 of bloodTemperature in 0oc
12036.4
220.536.6
32536.7
427.536.8
53036.7
632.536.6
73536.8
84036.7
94836.6
105636.8
116436.7
127236.6
138036.4
141702036.3
151405036.6
16808037.0
177013037.2
186517037.0
196016037.1
206515037.15
2113013037.2
2214011037.1
231309037.0
241007037.1
25805037.2
26602037.0
272036.4

a). Using the same axis draw graphs of oestrogen and progesterone against time/days  (8mks)

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