NAME...............................…………………………….…………… REG. NO……………...……….

SIGNATURE ...................................................................

P530/3
Biology Paper
(Practical Paper 3)
July/August 2023
3 ¼ Hours

ACEITEKA MOCK EXAMINATIONS 2023

INSTRUCTIONS TO CANDIDATES:
 This paper consists of three sections
 Answer all questions
 Answers must be written in the spaces provided. Additional sheets of paper must not be
inserted in this booklet.
 You are not allowed to start working with in the first 15minutes. You are instead advised
to use this time to read through the paper and ensure that you have all the apparatus,
chemicals and specimens you may require.

For Examiner’ Use Only

1
1. Question 1
You are provided with specimen K which has been freshly killed.
(a) Display the specimen on the dissecting dish in the usual way, Dissect the specimen to
release the skin on the ventral side.
i) Draw the superficial structures in the neck throat and thorax and label only the secretory
structures. (07½ marks)

ii) For each of the labelled structures, state the secretion and its role in the life of the
animal. (04marks)

...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................

2
(b) By further dissection, display the thoracic structures. Continue your dissection to expose
the structures of air passage and trace the route of blood to the head and fore limbs by
clearing off the neck muscles and biceps muscles. Draw and label your dissection without
displaying any organ. (22 marks)

3
2. Question 2
You are provided with solutions L, M and N which are extracts from seedlings at different
stages of germination. L and M are from the same type of seed.
(a) i) Carry out the following tests in tables 1, 2 and 3 to determine the nutrient content of
each solution. Record your tests, observation and deductions in the tables.
Table 1.
Iodine Test Observations Deductions
L

(07marks)
Table 2.

Iodine Test Observations Deductions

(07marks)

4
Table 3.
Biuret Test Observations Deductions
L

(07marks)
ii) From your results in the 3 tables above, explain the pattern of nutrient distribution in
extracts L and M. (03 marks)
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
(b) i) To 4cm3 of solution M, add 3cm3 of solution N in a test-tube. Incubate at 35-40°C for
30 minutes. After the time duration, carry out the tests in the table 4 on the content of the
test tube to establish the effect of one extract onto the other. Record your observations and
deductions.
Table 4.
Name of test Observations Deductions
Iodine

Reducing sugars

Biuret

(07marks)

5
 ii) Relate your above results of the experiment to the physiology of germination. (04 marks)
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................

iii) Suggest why preliminary tests were carried out on the extract before mixing them.
(04 marks)
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................

Question 3
You are provided with specimens P, Q, R, S, T and U. Examine the external structures of
specimens using a hand lens/ low power magnification.
(a) State three structural characteristics common to all the specimens. (03 marks)
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................
...................................................................................................................................................

(b) Observe under low powder magnification and describe the structural features of the
mouth parts of the following specimens, relating the structure to the function. (06 marks)
i) Specimen P
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
6
ii) Specimen U
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................

(c) Observe the mouth parts of specimen R under low power. Draw and label fully.
(07 marks)

(d) Using a hand lens give three structural similarities and differences in the features
observed on the hind limbs of specimens R and S. (06marks)

i) Similarities
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................

7
ii) Differences

R S

(e) By limiting yourself to the structures used for locomotion and sensitivity, construct a
dichotomous key to identify the specimens in the order P to U. (08marks)

......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................

......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
..................................................................................................................................................
......................................................................................................................................................
.....................................................................................................................................................

......................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................
.....................................................................................................................................................
......................................................................................................................................................
......................................................................................................................................................

⋆⋆⋆⋆End⋆⋆⋆⋆