Biology Paper 3 Questions and Answers with Confidentials - Bunamfan Cluster Pre Mock Exam 2022

Instructions to Candidates

• Spend the first 15 minutes of the time allocated to read through the question paper before commencing your work
• Answer ALL the questions in the spaces provided.

Questions

You are provided with the following materials;  

• Specimen A
• Scalpel
• 50ml beaker
• Glass rod
• 8cm visking tubing
• 2 pieces of strings
• 20ml distilled water in a wash bottle
• 100ml beaker
• 10ml Iodine solution
  
  
  1. You are provided with a specimen labeled A. Make a transverse section of the specimen.
     1. Draw and label the section (3mks)
     2. What type of fruit is specimen A? (1mk)
     3. Slice off about 2cm thick disc from the specimen. Peel it. Place the piece into a beaker and mash it into a paste using a glass rod. Add 20ml of distilled water and stir. Tie one end of the transparent tubing provided. Decant the extract into the tubing and tie the other end tightly, ensuring there is no leakage.
        Immerse the tubing with its contents in a 100ml beaker containing Iodine solution for 20 minutes.
        1. Record your observations in the table below (4mks)
           

           	Extract inside visking tubing	Iodine solution outside the visking tubing
           Before the experiment
           After the experiment

        2. Explain the results obtained from c(i) above. (5mks)
  2. Study the photographs below and answer the questions that follow.
     
     
     1. With observable reasons identify the class of the specimen in the photograph .
        1. Class…………………………………………………………………………..(1mk)
        2. Reasons (2mks)
     2.    
        1. Name the structures labeled (4mks)
           P …………………………………………
           Q …………………………………………
           R …………………………………………
           S …………………………………………
        2. State the function of the parts labeled (2mks)
           U ……………………………………………
           V …………………………………………
     3. Study the photographs below depicting plants growing in different habitats.
        
        
        1. Identify the habitats in which they are found (2mks)
           Y …………………………………………
           Z …………………………………………
        2. State the significance of the following structures found in the specimens shown above (2mks)
           R …………………………………………
           S …………………………………………
  3. Below are photographs showing some observable features of animals
     
     
     1. Using the features in the order given below, construct a dichotomous key that can be used to identify the specimens in the photographs. (10mks)
        • Presence or absence of backbone
        • Presence or absence of wings
        • Presence or absence of scales
        • Presence or absence of pouch
        • Bipedal or quadripedal
     2. Study the photographs below showing blood vessels in man.
        
        
        1. Using observable features identify the blood vessels (2mks)
           E …………………………………
           F ……………………………………
        2. Using observable features only, give two differences between the two blood vessels (2mks)
           

           E	F

Confidentials

• Each candidate will require the following

Question 1
You are provided with the following materials;

• Specimen A –Ripe banana
• Scalpel
• 50ml beaker
• Glass rod
• 8cm visking tubing
• 2 pieces of strings
• 20ml distilled water in a wash bottle
• 100ml beaker
• 10ml Iodine solution

Marking Scheme

Instructions to Candidates

• Spend the first 15 minutes of the time allocated to read through the question paper before commencing your work
• Answer ALL the questions in the spaces provided.
• Additional pages must not be inserted

1. You are provided with a specimen labeled A. Make a transverse section of the specimen.
   1. Draw and label the section (3mks)
      
   2. What type of fruit is specimen A? (1mk)
      • Berry
   3. Slice off about 2cm thick disc from the specimen. Peel it. Place the piece into a beaker and mash it into a paste using a glass rod. Add 20ml of distilled water and stir. Tie one end of the transparent tubing provided. Decant the extract into the tubing and tie the other end tightly, ensuring there is no leakage.
      Immerse the tubing with its contents in a 100ml beaker containing Iodine solution for 20 minutes.
      1. Record your observations in the table below (4mks)
         

         	Extract inside visking tubing	Iodine solution outside the visking tubing
         Before the experiment	White/cream/ pale yellow	Brown/ yellow
         After the experiment	Blue black	Brown/ yellow

      2. Explain the results obtained from c(i) above. (5mks)
         • Iodine molecules in the beaker moved into the visking tubing by diffusion; reacted with starch to give the blue black colour;
         • Colour of Iodine outside the visking tubing remains unchanged; because starch has large molecules; that can not diffuse through the semi-permeable; membrane of the visking tubing
2. Study the photographs below and answer the questions that follow.
   1. With observable reasons identify the class of the specimen in the photograph .
      1. Class -  Mammalia (1mk)
      2. Reasons
         • Presence of fur/hair
         • Presence of external ear
   2.        
      1. Name the structures labeled (4mks)
         • P Liver
         • Q Small intestines/ileum
         • R Stomach
         • S Pancreas
      2. State the function of the parts labeled (2mks)
         • U Secrete saliva
         • V harbours/contains bacteria that secrete cellulose enzyme that digests cellulose
   3. Study the photographs below depicting plants growing in different habitats.
      1. Identify the habitats in which they are found (2mks)
         • Y Fresh water
         • Z Dry/arid/semi arid/desert
      2. State the significance of the following structures found in the specimens shown above (2mks)
         • R Prick/injure/irritate/harm herbivores/animals
         • S Fills with air for buoyancy
3. Below are photographs showing some observable features of animal
   1. Using the features in the order given below, construct a dichotomous key that can be used to identify the specimens in the photographs. (10mks)
      • Presence or absence of backbone
      • Presence or absence of wings
      • Presence or absence of scales
      • Presence or absence of pouch
      • Bipedal or quadripedal
        
        1(a) Animals without a backbone………………………….Scorpion
        Animals with a backbone……………………………………go to 2
        2(a) Animals with wings………………………………………Eagle
        (b) Animals without wings…………………………………go to 3
        3(a)Animals with scales……………………………………Monitor lizard
        (b)Animals without scales…………………………………go to 4
        4(a) Pouch present…………………………………………Kangaroo
        (b)Without a pouch…………………………………………go to 5
        5(a) Bipedal ………………………………………………Man
        (b) Quadripedal………………………………………………Gorilla
   2. Study the photographs below showing blood vessels in man.
      1. Using observable features identify the blood vessels (2mks)
         • E Vein
         • F Artery
      2. Using observable features only, give two differences between the two blood vessels (2mks)
         

         E	F
         Wide lumen	Narrow lumen
         Thin wall	Thick wall
         Presence valve	Valve absent