KCSE 2026 MOCK EXAMS ALL SUBJECTS NEW !!!100% GUARANTEED PASS A+

KCSE 2026 MOCK EXAMS

ALL SUBJECTS

A Joint Cluster Examination Trial for KCSE Candidates among
selected Top Performing National Schools in the Republic of
Kenya.

SUBJECTS TESTED;
Mathematics, English, Kiswahili, Biology, Chemistry, Physics, Geography,
CRE, History, Business Studies, Home-science, Agriculture, IRE
& Computer Studies.




SERIES 2

, KCSE 2026 MOCK EXAMINATIONS
SERIES 2
231/1

BIOLOGY
PAPER 1 (THEORY)
TIME: 2 HOURS

NAME……………………………………………………………………………………….

SCHOOL……………………………………………… SIGN………………………..

INDEX NO……………………………………………. ADM NO……………………



(Kenya Certificate of Secondary Education)

INSTRUCTIONS TO THE CANDIDATES
 Write your name and admission number in the spaces provided above
 Write the name of your school and the date of examination in the spaces provided above
 Answer ALL the questions in the spaces provided.
 Answers must be written in the spaces provided in the question paper.
 Additional papers must not be inserted.
 Candidates should answer the questions in English.


FOR EXAMINER’S USE ONLY
QUESTION MAXIMUM SCORE CANDIDATE’S SCORE



1-31 80




MR FGMPG

, Answer ALL the questions in the spaces provided.
1. Two students were observing bacteria using identical microscopes and identical slides. Student
A saw 10 bacteria and student B saw 50 bacteria.
a) Suggest a reason why they observed different number of bacteria. (1 mark)
………………………………………………………………………………………………………
………………………………………………………………………………………………………


b) Which of the following combination would give a wider field of view, eye piece X10 and
objective lens X20 or eye piece X10 and objective lens X40? (1 mark)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………


2. The diagram below represents a cell organelle.




i) Identify the organelle (1 mark)
………………………………………………………………………………………………………
ii) State the function of the organelle (1 mark)
………………………………………………………………………………………………………


3. A plastic bottle full of water was stoppered using a piece of stem obtained from a young
herbaceous plant whose epidermis had been peeled off. After 24 hours, it was noted that the
stopper closed the container tightly.
a) Why was the epidermis peeled? (1 mark)
………………………………………………………………………………………………………
………………………………………………………………………………………………………

MR FGMPG

, b) Account for the observation made (2 marks)
………………………………………………………………………………………………………
………………………………………………………………………………………………………
………………………………………………………………………………………………………


4. Give the roles of the following in the alimentary canal:
a) Hydrochloric acid in the stomach (1 mark)
………………………………………………………………………………………………………
………………………………………………………………………………………………………


b) Mucus (1 mark)
………………………………………………………………………………………………………
………………………………………………………………………………………………………


c) Name the cells that secrete enzyme pepsin and renin in the stomach (1 mark)
………………………………………………………………………………………………………


d) Enzyme enterokinase activates trypsinogen to trypsin. Give the origin of the enzyme
(1 mark)
………………………………………………………………………………………………………




5. Give the roles of the following hormones: (2 marks)
i) Secretin
………………………………………………………………………………………………………
………………………………………………………………………………………………………


ii) Cholecystokinin
………………………………………………………………………………………………………
………………………………………………………………………………………………………


MR FGMPG