Term 3 Form 4 Biology Exam Paper 2
- The diagram below shows a structure found in the ileum.
- Identify the structure. (1 mk)
- State the functions of the structure. (2 mks)
- Identify and state the functions of the part labelled B. (2 mks)
- Explain how the structure is adapted to its functions. (3 mks)
The figures below illustrate two types of fruits S and T.
- Give the class of fruits represented by both figures S and T. (1 mk)
- Give one feature of the class mentioned above. (1 mk)
- Identify the type of placentation found in the fruits shown. (2 mks)
S
T
- i) Identify the type of fruits S and T. (2 mks)
S
T
ii) Give a reason for each answer in 2d(i) above. (2 mks)
S
T
The figures below illustrate four different types of beaks found in birds that are adapted to different modes of feeding.
- State the concept demonstrated by the above beaks. (1 mk)
- Give the name used to describe structures which have evolved through the above process. (1 mk)
- State the evidence of evolution depicted by the four types of beaks. (1 mk)
- Suggest the birds that occupy the 2nd trophic level. (2 mks)
- Explain why an insect and a bird cannot be said to have evolutionary relationship even if both have wings for flight. (2 mks)
.
- State two theories that explain the origin of life. (2 mks)
- Two normal parents gave birth to a son. As the son grew up, the parents found out that he always picked a red jersey when going to school yet the school required a green jersey. The parents tried to explain to the boy the mistake but the boy could not understand.
- Identify the genetic condition that the boy could be suffering from. (1 mk)
- Give the possible genotypes of the two parents towards that condition. (Use letter N to represent the normal gene). (2 mks)
- Using a punnet square, determine the boy’s genotype. (4 mks)
- Give the genetic term used to refer to characteristic inherited in the above manner. (1 mk)
- The diagram below shows an experimental set-up to investigate a certain physiological process in plants.
- State the aim of the experiment. (1 mk)
- State the role of the following in the experiment
- Potassium hydroxide (1 mk)
- Aluminum foil (1 mk)
- Calcium hydroxide in test tube B. (1 mk)
- Account for the expected colour change in test-tube C. (2 mks)
- State two raw materials for photosynthesis. (2 mks)
SECTION B
Answer question 6 (compulsory) and either question 7 or 8 in the spaces provided.
- A scientist carried out a population study of two types of moths in a given region in England.
He placed a transect of about 20 miles starting from an old oil refinery and sampled average population of the two types of moths per square kilometer. The data collected is shown in the following table.
| Distance from the oil refinery (in km) | Average pop. Of white peppered moths (in thousands per km2) | Average pop of dark peppered moths (in thousand per km2) |
| 2 | 24 | 300 |
| 4 | 40 | 300 |
| 6 | 74 | 282 |
| 8 | 130 | 250 |
| 10 | 204 | 194 |
| 12 | 252 | 154 |
| 14 | 260 | 80 |
| 16 | 260 | 54 |
| 18 | 260 | 40 |
| 20 | 260 | 18 |
- Using the same axis, plot graphs of population of the two types of moths against distance from the oil refinery. (6 mks)
- From the graph, determine the number of moths of each type at a distance of 4.5km from the refinery. (2 mks)
- From the graph, determine the distance at which the white peppered moths would have a population of 164,000 per km2. (1 mk)
- At what distance from the refinery were the two populations equal? (1 mk)
- Account for the populations of the two moths at the following distances
- 2 to 6km (3 mks)
- 14 to 20km (4 mks)
- Explain the evolutionary theory behind the observation in the study. (3 mks)
- Describe the role of hormones in growth and development of plants. (20 mks)
Describe the adaptation of the mammalian skin to its function. (20 mks)