TOP BIOLOGY NATIONAL SCHOOLS
AND JOINT MOCKS 2021
231/1 (Kenya Certificate of Secondary Education) Paper 1
INTERNAL MOCK EXAM
BIOLOGY
Dec. 2020– 2 Hours
Name…………………………………………………… Index No. …………………………
Adm No………………………………………………… Date:……………………………………………………
Signature ……………………………………………… Stream :………………………………………………
Instructions to candidates
a) Write your Name, Index, Admission number and stream in the spaces provided above.
b) Sign and write the examination date on the spaces provided above.
c) Answer all questions in the spaces provided in the question paper.
d) All workings must be clearly shown where necessary.
e) Candidates should check the question paper to ascertain that all the pages are printed as
indicated and that no questions are missing.
f) Candidates must answer the questions in English.
QUESTIONS MAXIMUM SCORE CANDIDATE SCORE
1-27 80
For Examiners use
1 FOR MARKING SCHEMES INBOX OR TEXT O724351706
,1. Explain why malaria cannot be transmitted through blood transfusion. (2 marks)
2. A boy held a locust upside down and attempted to drown it in water by immersing the head in water. Was
he successful? (1 mark)
Explain. (2 marks)
3. The diagram below shows the position of an image formed in a defective eye.
(a) Name the defect: (1 mark)
(b) Explain how the defect named in (a) above can be corrected. (2 marks)
(b) Using a sketch, draw to demonstrate how the above condition is corrected. (1 mark)
4. State two ways in which scales are adapted to their function. (2 marks)
5. (a) What is the name given to two protrusions on the posterior end of the skull, that articulate to the
atlas. (1 mark)
(b) Give the name of the joint formed in (i) above, and state its functions. (1 mark)
Joint: ...............................................................................................................................
Function: ..............................................................................................................................
6. (i) What is emulsification? (1 mark)
(ii) Name two emulsifying agents found in the human bile. (2 marks)
7. The diagram below represents part of alimentary canal. Study it and use it to answer the questions that
follow.
2 FOR MARKING SCHEMES INBOX OR TEXT O724351706
, (i) Identify the diagram shown above. (1 mark)
(ii) Name the parts labelled J and L. 2MKS
(iii) What are the components of the substance produced by part labeled K. (1 mark)
8. Describe the events that costitutes the crossing over . (3 marks)
9. The diagram below shows the part of gaseous exchange structures in human.
State three roles of the nasal cavity in human. (3 marks)
10. (a) Distinguish between complete dominance and incomplete dominance. (2 marks)
(b) Give an example of a characteristic trait that is inherited under incomplete dominance.
(1 mark)
12. (a) In 1953, S.L Miller carried out an experiment to explain which theory in evolution? (1 mark)
(b) What is meant by vestigial structures? (1 mark)
(c) Give an example of a vestigial structure in human. (1 mark)
13. (a) What do you understand by the term exoskeleton. (1 mark)
(b) State the name of two tissues that constitutes the endoskeleton. (2 marks)
(c) State the name of the phylum where the exoskeleton is found. (1 mark)
14. (a) Observe the diagram below to answer the questions that follows.
3 FOR MARKING SCHEMES INBOX OR TEXT O724351706
, (a) State the name of the condition shown in the diagram above. (1 mark)
(b) Name the type of fins that prevents the condition named in 14 (a) above. (2 marks)
15. The diagram below represents a sketch of certain organism found in a store room of food stuff in most
homes.
(a) State the branch of biology that deals with the study of the above organisms. (1 mark)
(b) Name the type of cell division that takes place at part labelled S. (1 mark)
(c) Identify part labeled V and state their function.
V ............................................................................................................... (1 mark)
Functions .................................................................................................. (1 mark)
16. Distinguish between obligate anaerobes and facultative anaerobes. (2 marks)
17. Giving examples, state two ways in which biological nitrogen fixation is carried out. (4 mark)
18. (a) State one sample counting method which is not suitable in a densely forested habitat.
(1 mark)
(b) The information below shows how a student took information in order to estimate the population of
beetles in a field. Estimate the population. (2 marks)
19. State three aspects of growth that can be estimated in living organisms. (3 marks)
20. Giving examples, explain what you understand by cranial nerves. (3 marks)
21. Give two external features of members of class Aves. (2 marks)
22. (a) What do you understand by the term Lichen with reference to ecology? (2 marks)
4 FOR MARKING SCHEMES INBOX OR TEXT O724351706
AND JOINT MOCKS 2021
231/1 (Kenya Certificate of Secondary Education) Paper 1
INTERNAL MOCK EXAM
BIOLOGY
Dec. 2020– 2 Hours
Name…………………………………………………… Index No. …………………………
Adm No………………………………………………… Date:……………………………………………………
Signature ……………………………………………… Stream :………………………………………………
Instructions to candidates
a) Write your Name, Index, Admission number and stream in the spaces provided above.
b) Sign and write the examination date on the spaces provided above.
c) Answer all questions in the spaces provided in the question paper.
d) All workings must be clearly shown where necessary.
e) Candidates should check the question paper to ascertain that all the pages are printed as
indicated and that no questions are missing.
f) Candidates must answer the questions in English.
QUESTIONS MAXIMUM SCORE CANDIDATE SCORE
1-27 80
For Examiners use
1 FOR MARKING SCHEMES INBOX OR TEXT O724351706
,1. Explain why malaria cannot be transmitted through blood transfusion. (2 marks)
2. A boy held a locust upside down and attempted to drown it in water by immersing the head in water. Was
he successful? (1 mark)
Explain. (2 marks)
3. The diagram below shows the position of an image formed in a defective eye.
(a) Name the defect: (1 mark)
(b) Explain how the defect named in (a) above can be corrected. (2 marks)
(b) Using a sketch, draw to demonstrate how the above condition is corrected. (1 mark)
4. State two ways in which scales are adapted to their function. (2 marks)
5. (a) What is the name given to two protrusions on the posterior end of the skull, that articulate to the
atlas. (1 mark)
(b) Give the name of the joint formed in (i) above, and state its functions. (1 mark)
Joint: ...............................................................................................................................
Function: ..............................................................................................................................
6. (i) What is emulsification? (1 mark)
(ii) Name two emulsifying agents found in the human bile. (2 marks)
7. The diagram below represents part of alimentary canal. Study it and use it to answer the questions that
follow.
2 FOR MARKING SCHEMES INBOX OR TEXT O724351706
, (i) Identify the diagram shown above. (1 mark)
(ii) Name the parts labelled J and L. 2MKS
(iii) What are the components of the substance produced by part labeled K. (1 mark)
8. Describe the events that costitutes the crossing over . (3 marks)
9. The diagram below shows the part of gaseous exchange structures in human.
State three roles of the nasal cavity in human. (3 marks)
10. (a) Distinguish between complete dominance and incomplete dominance. (2 marks)
(b) Give an example of a characteristic trait that is inherited under incomplete dominance.
(1 mark)
12. (a) In 1953, S.L Miller carried out an experiment to explain which theory in evolution? (1 mark)
(b) What is meant by vestigial structures? (1 mark)
(c) Give an example of a vestigial structure in human. (1 mark)
13. (a) What do you understand by the term exoskeleton. (1 mark)
(b) State the name of two tissues that constitutes the endoskeleton. (2 marks)
(c) State the name of the phylum where the exoskeleton is found. (1 mark)
14. (a) Observe the diagram below to answer the questions that follows.
3 FOR MARKING SCHEMES INBOX OR TEXT O724351706
, (a) State the name of the condition shown in the diagram above. (1 mark)
(b) Name the type of fins that prevents the condition named in 14 (a) above. (2 marks)
15. The diagram below represents a sketch of certain organism found in a store room of food stuff in most
homes.
(a) State the branch of biology that deals with the study of the above organisms. (1 mark)
(b) Name the type of cell division that takes place at part labelled S. (1 mark)
(c) Identify part labeled V and state their function.
V ............................................................................................................... (1 mark)
Functions .................................................................................................. (1 mark)
16. Distinguish between obligate anaerobes and facultative anaerobes. (2 marks)
17. Giving examples, state two ways in which biological nitrogen fixation is carried out. (4 mark)
18. (a) State one sample counting method which is not suitable in a densely forested habitat.
(1 mark)
(b) The information below shows how a student took information in order to estimate the population of
beetles in a field. Estimate the population. (2 marks)
19. State three aspects of growth that can be estimated in living organisms. (3 marks)
20. Giving examples, explain what you understand by cranial nerves. (3 marks)
21. Give two external features of members of class Aves. (2 marks)
22. (a) What do you understand by the term Lichen with reference to ecology? (2 marks)
4 FOR MARKING SCHEMES INBOX OR TEXT O724351706
