Question 1
(a) Complete the table below by stating the conditions and methods of reproduction
of the organisms in the table.
organism |
Condition for reproduction |
Method of reproduction |
Bacterium |
|
|
Virus |
|
|
Fungus |
|
|
Moss |
|
|
Plant |
|
|
[10 marks]
(b) (i) What is transpiration in plants?
[2 marks]
(ii) State three environmental factors that may affect the rate of transpiration
in plants.
[3 marks]
(iii) Explain briefly the role of stomata in transpiration.
[3 marks]
(iv) State two ways by which transpiration is importance to plants.
[2 marks]
Observation
Some candidates that attempted this question performed well in providing the condition for reproduction in fungi and moss, while most of them could not give the condition for reproduction in bacteria.
Some candidates could not state the correct environmental factors that affect the rate of transpiration in plants.
Candidates failed to state the opening and closing of stomata and the effects on plants.
The expected answers are:
- (a) Table
Organism |
Condition for reproduction |
Method of reproduction |
Bacterium |
Suitable temperature; availability of nutrients |
Binary fission/fission/asexual reproduction |
Virus |
A living host/cell |
Replication |
Fungus |
Moist/damp/substrate/suitable temperature |
Asexual reproduction/spore formation/sporulation/budding Sexual/conjugation/oidia formation/zomatogamy |
Moss |
Presence of water/ moisture |
Asexual |
Plant |
Sunlight, water moisture, nutrients |
Asexual/vegetative |
10x1[10 marks]
(b) (i) Transpiration
This is the process by which water is lost as vapour; from the leaves/plant /stomata/lenticel.
2x1[2 marks]
(ii) Environmental Factors that Affect the Rate of Transpiration
- light intensity;
- humidity;
- air movements/wind;
- temperature.
Any 3x1[3marks]
(iii) The Role of Stomata in Transpiration
Stomata close up to reduce the rate of water loss in a leaf; open up to increase the rate of
water loss.
2x1[2 marks]
(iv) Importance of Transpiration
- it gives a cooling effect to the leaf/plants when it is exposed to sunlight;
- a water flow may be needed to obtain mineral salts;
- maintains transpiration pull;
- it removes excess water from the plant.