Biology Paper 3 with Confidential Questions and Answers - Lanjet Joint Mock Exams 2020

INSTRUCTIONS TO CANDIDATES

• Answer all the questions.
• You are required to spend the first 15 minutes of the 1¾ hours allowed for the paper reading the whole paper carefully before commencing your work.
• Answers must be written in the spaces provided in the question paper.
• Additional pages must not be inserted.
• This paper consists of 5 printed pages. Candidates should check to ensure that all pages are printed as indicated and no questions are missing

1. The diagram below illustrates the life cycle of a certain organism.
   
   
   1.    
      1. Giving reasons, name the division to which the organism belongs.
         Division………………………………………………………………………………(1mark)
         Reasons (2marks)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
      2. Which portion of the plant’s life is independent? (1mark)
         ………………………………………………………………................................................................................................................................................................…………………………………………
   2.     
      1. Name the parts labeled A and B. (2marks)
         A…………………………...............................……………………………………………….
         B…………………………................................………………………………………………
      2. State one function of the part labeled B. (1mark)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
      3. Define the term alternation of generation. (1mark)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………................................................................................................................................................................………
      4. Identify the generations labeled K and L. (2marks)
         Q …………………………………………………………………………….
         Z ……………………………………………………………………………
      5. In what way is generation L advantageous to generation K? (2marks)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
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      6. Give a reason why the plant shown in the diagram above is common in swampy areas (2marks)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
2. You are provided with several specimens N and indicator D, which is Bromolthymol blue. Study them and answer the questions that follow:
   1.    
      1. Identify the part of plant represented by specimen N. (1mark)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………
      2. Give a reason for your answer in a) i) above. (1mark)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
   2.    
      1. Name the physiological process which is taking place in specimen N. (1mark)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
      2. Describe the two changes which occurred to specimen N during the process named in b) i) above. (2marks)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
         .....…………………………………………………………………………………………………………
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   3.    
      1. State two internal factors which would promote the physiological process exhibited by specimen N, (2marks)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
         .....…………………………………………………………………………………………………………
      2. State two external conditions which would inhibit the process demonstrated by specimen N.(2marks)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
         .....…………………………………………………………………………………………………………
   4. Add 1ml of indicator marked D into a test tube, add 6 pieces of specimen N into the test tube. Close the mouth of the test tube tightly using a tissue paper. Leave the set up to stand on the tube rack for 30 minutes after which carefully remove specimen N without pouring the indicator marked D using a wooden splint.
      
      1. Record your observation after 30 minutes (1mark)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
      2. Account the observation in d) i) above (3marks)
         .....…………………………………………………………………………………………………………
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      3. Suggest a control for his experiment. (1mark)
         .....…………………………………………………………………………………………………………
         ……………………………………………………………………………………….....…………………
3. You are provided with photograph L, K and J. Examine them.
   
   
   1. Using observable features only, state class of animals shown in the photograph L and K. (4 marks)
      L
      Class ………………………………………………………………………………………………
      Reason……………………………………………………………………………………………
      K
      Class ………………………………………………………………………………………………
      Reason…………………………………………………………………………………………….
   2.    
      1. On the photograph J name the parts labeled E, F and G. (3 marks)
         E..............………………………………………………………………………………………………
         F..………………………………………………………………………………………………………
         G.....……………………………………………………………………………………………………
      2. State the functions of the structures labeled H in photograph J. (2marks)
         ..…………………………………………………………………………………………………………………………………………………………..………………………………………………………………………………………………………………..……………………………………………………
   3.    
      1. The actual length of animal J in cm is shown by a section of the ruler in the photograph.
         Calculate the tail power (show your working) (2marks)
      2. State the significance of tail power to the life of fish in water. (1mark)
         …………………………………………………………………………………………………………
         …………………………………………………………………………………………………………

CONFIDENTIAL INSTRUCTIONS TO SCHOOLS

The information contained in this paper is to enable the head of the school and the teacher in charge of biology to make adequate preparations for this year’s Lanet Joint Examination in Biology practical Examination.
No one Else should have access to this paper or acquire knowledge of its contents. Great care MUST be taken to ensure that the information herein does not reach the candidates either directly or indirectly.
The teacher in charge of Biology should NOT perform any of the experiments in the same room as the candidates or give any other information related to the experiments to the candidates.
Each Candidate will require:

• a test tube
• Test tube rack
• Soaked pea seeds with only radicle visible, marked N.----6pcs per student
• 10ml measuring cylinder
• A small piece of tissue paper for closing the test tube mouth
• A Wooden splint
• Bromothymol blue 2ml per student, marked D

MARKING SCHEME

Question 1

1.    
   1. Pteridophyta
      Reasons
      • It has fronds
      • Body differentiated into roots, stems and leaves but no flowers.
      • Has sori.
   2. K
2.    
   1. A-Rhizome
      B. Sori
   2. It contains sporangia that bear spores
3.    
   1. presence of gametophyte phase and sporophyte phase in lifecycle of an organism.
   2. Q – Gametophyte
      Z- Sporophyte
   3. Produces haploid male and female gametes, that undergo fertilization to produce zygote that develops into a sporophyte.

Question 2

1.    
   1. Seed; (1mk)
   2. It has one scar / point of attachment to placenta (1mk)
2.    
   1. Germination; (1mk)
   2. Water moves into the seed through the micropyle by imbitions; the seed swells; stored food become hydralised / enzyme break down the stored food into soluble products; the embryo uses the soluble nutrients leading to radical coming out through the micropyle; (3mks)
      mature embryo
3.  
   1. Absence of growth inhibitors
   2. Presence growth hormones;
      soft / permeable testa; (1st 2 point , 2mks)
4.    
   1. Absence of light of specific wavelength;
      Low / freezing / chilling temperature
      Lack of moisture (1st 2 point, 2mks)
      The indicator D turned yellow;
   2. The soaked seeds carry out respiration; which produces CO₂ which in turn changes the indicator from blue to yellow; (3mks)
   3. Use boiled seeds / dry seed; (1mk)

Question 3

1. L – mammalia
   Body is covered with fur
   K – Aves
   Has a beak
   Body covered with feathers
2. E- dorsal fin
   F – Operculum
   G – Pectoral fin
   1. Overlaps facing backwards to reduce friction for the fish as it moves in water
   2. Covered with mucus to reduce friction for the fish as it moves in water