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Form 3 Biology Paper 3 End of Term 2 Examination 2022

Class: Form 3

Subject: Biology

Level: High School

Exam Category: Form 3 End Term 2 Exams

Document Type: Pdf

    

Views: 566     Downloads: 42

Exam Summary


1. You are provided with the following reagents and materials.
- Specimen R
- Iodine solution
- Benedict’s solution
- Sodium hydroxide solution
- Copper sulphate solution
- Source of heat
- 3 test tubes in a rack
- Droppers
- Scalpel/Razor blade
- Pestle and mortar
Study the specimen R provided.
(a) Identify the type of fruit. (1 mark) …………………………………………………………………………………………
(b) With reasons, identify the method of dispersal for the specimen. Method of dispersal (1 mark) ………………………………………………………………………………………… Reasons (2 marks) ……………………………………………………………………………………….. ………………………………………………………………………………………… …………………………………………………………………………………………
(c)
 By use of the scarpel provided, peel off the outer cover of the specimen R to reveal the inner juicy part.
 Extract a small portion of the juicy part, place in a mortar and smash it using a pestle.
 Decant the juicy extract from the crushed specimen R into a test tube.
 Divide the juicy extract from specimen R into two portions each 2cm3 and use them as follows;
Portion one Use the reagents provided to test for the food substances present in portion 1. Use the table below as a guide. (6 marks)
1.png
Portion two
(d) (i) To 1cm3 of DCPIP in a test tube, add 0.1% solution of Ascorbic acid drop by drop until the colour of DCPIP disappears. Shake the test tube after addition of each drop. Record the number of droplets used. (1 mark) …………………………………………………………………………………
ii) To another 1cm3 of DCPIP in a test tube add the portion two drop by drop, shaking the test tube after addition of each drop until the colour of DCPIP disappears. Record the number of drops used (1 mark) …………………………………………………………………………………
iii) From the results obtained in (d) (i) and (ii) above, calculate the percentage of Ascorbic acid in the juice obtained from specimen R. Show your working (2 marks) ………………………………………………………………………………………… …………………………………………………………………………………………. ………………………………………………………………………………………… …………………………………………………………………………………………..
2. (a)You are provided with specimens labeled K and L obtained from the same mammal.
(i) Identify specimens K and L (2mks) Specimen K: …………………………………………….. Specimen L: ………………………………………………
(ii) State the functions of specimens K and L. (2mks) Specimen K:………………………………………………….. Specimen L:……………………………………………….
(iii)Give two adaptations of specimen L to its function. (2mks) ………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………
(iv)Give two differences between specimens K and L. (2mks)
(b).Study the photographs below and answer the questions that follow.
2.png
(i)With observable reasons, identify the classes of specimen X and Z Specimen X Class ………………………………………………………………………………… (1 mark)
Reason (1 mark) …………………………………………………………………………………………………
Specimen Z Class (1 mark) ………………………………………………………………………………………………… Reason s (2 marks) ……………………………………………………………………………………………....
(ii)Describe two adaptations of organism labeled Y to its habitat. (2 marks)
3.png
3.Below are photographs labelled W and J of organs obtained from different animals. The organs perform similar functions. Examine them Photograph W Photograph J
4.png
(a).(i)Identify the organs. (2 marks) Photograph J………………………………………………… K.................................................................................................
(ii) Identify the following parts on photograph W? (2 marks) M ...…………………………………………………………………………………………
L …………………………………………………………………………………………..
(ii) Give two adaptations of the part labeled M on photograph W. (2 marks) ………………………………………………………………………………………………… …………………………………………………………………………………………………
(b.) (i)Name the class to which the organs on photograph J was obtained from (1 mark) …………………………………………………………………………..
(ii)Identify the parts labelled 1 and 3 in photograph J. (2 marks) 1…………………………………………………………………………….. 3…………………………………………………………………………….
(c) Using observable features, state how the part labelled1 you identified in (b),(ii) above is adapted to its functions (1 marks) ………………………………………………………………………………… ………………………………………………………………………………….. ……………………………………………………………………………………
(d) .State the general function performed by both organs. (1 mark) …………………………………………………………………………… ……………………………………………………………………………

 

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