Term 3 Form 4 Biology Exam Paper 1

1. The name Ipomea Kituiensis belongs to a creeping plant found in Kitui district.

Identify;

1. The species name of the plant. (1 mk)

 

1. The generic name where the plant belongs. (1 mk)
2. How was the term Kituiensis derived? (1 mk)

 

1. The equation below represents a process during which a lipid is formed.

 

1. Name the units A and B.

• What is process C? (1 mk)

 

 

1. Identity the by-product D. (1 mk)
2. The following diagrams show the results of an investigation on strips of Bidens Pilosa stem which were at lengthwise from the main stem then placed in distilled water and salt solution.

 

1. Explain the results obtained in;
2. Distilled water (2 mks)

 

1. Salt solution (2 mks)
2. What process was being investigated? (1 mk)

 

1. The diagram below shows part of a starch molecule

1. State what the circles and lines joining them represent.
2. Circles (1 mk)

 

1. Lines (1 mk)

 

1. Name an enzyme that can act on this starch molecule to separate the circles from each other.

(1 mk)

 

2. Name the specific part of the human body that the brain will send nerve impulse or hormones to, for corrective measures to be taken if the blood passing through it has:
3. Too much water (1 mk)

 

1. Higher than normal carbon (IV) oxide (1 mk)

 

• Too little glucose (1 mk)

1. Differentiate between;
2. Cisternae and cristae (2 mks)
3. Organelles and organs (2 mk)

The diagram below represents the human elbow joint

1. Name the type of joint shown. (1 mk)
2. Name the parts labelled H and L.             (2 mks)

H

L

 

1. State the role of fluid in part K. (1 mk)

 

1. a) What are the three end products of anaerobic respiration in plants?              (3 mks)

 

1. Give two reasons why accumulation of lactic acid during vigorous exercise leads to an increase in heartbeat. (2 mks)

 

2. The diagram below represents a plant in division Bryophyta.

1. Name the parts labelled B and D (2 mks)

B _____________________________________________

D _____________________________________________

 

1. State one function for each of the parts labelled A and C. (2 mks)

A _________________________________________________________________________

C _________________________________________________________________________

 

1. A flower was found to have the following characteristics:

Inconspicuous petals

Long feathery stigma

Small, light pollen grains

1. What is the likely agent of pollination of the flower? (1 mk)

 

 

1. What is the significance of the long feathery stigma in the flower? (1 mk)

 

 

1. How do the male gamete nuclei reach the ovule after pollen grains land on the stigma? (1 mk)

 

 

2. The diagram below represents a stage during germination of a seed.

1. Name the type of germination illustrated in the diagram. (1 mk)

 

 

1. Name part X (1 mk)
2. State the role of the part X during germination of the seed.             (2 mks)

 

 

1. a) What is meant by the term sex-linkage?                                                          (1 mk)

 

 

1. b) Name two sex-linked traits in humans.                                     (2 mks)

 

 

2. a) Explain why certain drugs become ineffective curing a disease after many years of use. (2 mks)

 

1. State two limitations of fossils as an evidence of evolution. (2 mks)

 

1. What are vestigial structures? (1 mk)

 

3. A response exhibited by a certain plant tendril is illustrated below.

1. Name the type of response. (1 mk)

 

1. Explain how the response named in (a) above occurs. (3 mks)

 

1. State one importance of tactic response in euglena. (1 mk)

 

The diagram below shows the front view of the mammalian eye for a person in a brightly lit room.

1. Draw the change that would appear when this person moves from the brightly lit room to a dimly lit room. (Draw alongside the diagram above).                         (1 mk)

 

1. Name muscles A and B (2 mks)

A

B

 

1. Name the photoreceptor cells found in large numbers at the fovea centralis of the eye. (1 mk)

 

1. The graph below shows the growth pattern in an insect measured by increase in fresh weight.

1. What is the term given to describe this kind of growth? (1 mk)

 

 

1. Explain the changes that occur in the insect from point A to B on the graph with emphasies on what happens at point X. (2 mks)

 

1. Name the sequential stages in complete metamorphosis. (1 mk)

 

1. a) State two structural adaptations of lungs in mammals.                                   (2 mks)

 

1. b) What are spiracles?                                                                                         (1 mk)

 

2. a) State two changes that take place in the blood of a person who moves to a higher attitude area

to train in athletics.                                                                                         (2 mks)

 

1. By what mode of action do antibodies lysins destroy microscopic pathogens? (1 mk)

 

3. Below is a diagram of a sperm cell.

1. Identify parts labelled W and Y. (2 mks)

W

Y

 

1. Explain how part X is adapted to its functions. (1 mk)

 

1. Apart from the cell membrane, name the other membrane of the ovum. (1 mk)

 

1. a) State Mendel’s first law of inheritance.                                                                      (2 mks)

 

 

1. State two functions of the deoxyribonucleic acid. (2 mks)