Biology Paper 1 Questions - Mumias West Pre Mock Exams 2023

INSTRUCTIONS TO CANDIDATES

1. Read all questions and answer in the spaces provided.
2. Candidates should check the question paper to ascertain that all the pages are printed as indicated and that no questions are missing.
3. No blank spaces should be left during examination as they do not score.

QUESTIONS

1. State the function of:
   1. Ribosomes (1mk)
   2. Lysosomes (1mk)
2. State two ways in which a respiratory surface is adapted to its function. (2mks)
3. What is meant by the following term?
   1. Habitat (1mk)
   2. Ecosystem (1mk)
4. Explain why is not advisable to be in a poorly ventilated room with a burning charcoal. . (2mks)
5. The diagrams below show an experiment set up to investigate a certain process in a plant tissue.
   
   Explain the results obtained after 30 minutes. (3mks)
6. The diagrams below illustrate the organs of some flowering plants.
   
   State the classes of plants to which each belong. (2mks)
   A_______________________
   B_________________________
7. Give reasons for carrying out the following procedures when preparing temporary wet mounts of plant tissues.
   1. Making thin plant sections (1mk)
   2. Adding water on the plant section. (1mk)
8. The diagram below represents a transverse section of an ovary from a certain flower.
   
   
   1.                  
      1. Name the structure labeled W (1mk)
      2. Name the type of plantation illustrated in this diagram. (1mk)
9.                  
   1. The diagram below illustrates a germinating seedling
      
      
      1. Name the type of germination illustrated in the diagram (1 mark)
      2. Describe how the type of germination named in(i) above is brought about (3 marks)
   2. Name the gland that secretes the following hormones. (2mks)
      1. Ecdysone………………….
      2. Juvenile…………………..
   3. Give two sex linked genes found on the Y-chromosomes. (2mks)
   4. Below is a nucleotide strand
      

      A

      A

      G

      T

      C

      1. Identify the type of nucleic acid. (1mk)
      2. Give a reason for your answer in (i) above (1mk)
10. State two observable features that place a millipede into its class (2mks)
11. The diagram below illustrates tissue fluid and cells surrounding a capillary
    
    
    1. Name fluid G (1mk)
    2. Give two ways by which fluid G is different form tissue fluid (2 mks)
12.              
    1. Define respiration (1mk)
    2. Name two products of respiration in plants (2mks)
    3. State three activities in the human digestive system that depend on respiration (3mks)
13. State three ways in which blood capillaries are structurally adapted to their functions (3mks)
14. The diagram below represents an organ in a bony fish
    
    
    1. Name the organ (1 mk)
    2. Describe how air in water reach the capillaries inside structure L (3 mks)
15. During a practical investigation on food tests, students were provided with the following reagents:
    • Benedict’s solution
    • Sodium hydrogen carbonate
    • Dilute hydrochloric acid
      1. Identify the food substance the students were to test. (1 mark)
      2. State the role of hydrochloric acid and sodium hydrogen carbonate during the experiment.
         1. Dilute hydrochloric acid (1 mark)
         2. Sodium hydrogen carbonate (1 mark)
16. The table below shows the percentage concentration of certain substances in blood plasma glomerular filtrate and urine in a human being at a particular time.
    

    	Percentage concentration
    Substance	Blood plasma	Glomerular filtrate	Urine
    Glucose	0.023	0.02	0.0
    Water	92.70	92.70	96.08
    Protein	5.69	0.0	0.0
    Urea	0.087	0.098	2.6

    1. Explain the likely impact on the composition of urine in case of the following:
       1. Vigorous physical exercises (2 mks)
       2. A meal rich in proteins (2 mks)
    2. Name the processes responsible for:
       1. Presence of glucose in glomerular filtrate (1 mk)
       2. Absence of glucose in urine (1 mk)
17. The diagram below represents a set up during an experiment.
    
    
    1.            
       1. What was the experiment investigating? (1 mk)
       2. State the likely identity for substance K. (1 mk)
       3. Explain your answer in (a) (ii) above. (1 mk)
    2. Account for the observations made in flask 2. (2 mks)
18.                
    1. Beside venation, state two other external characteristics of leaves that can be used to classify plants. (2mks)
    2. How can floral parts be used to classify plants (2mks)
19.                  
    1. What is meant by the term seed dormancy? (1mk)
    2. State three causes of seed dormancy. (3mks)
20. Explain why;
    1. Mammalian testes are located to hang outside the body. (2mks)
    2. Four months after fertilization, ovaries can be removed from a human female, without terminating pregnancy. (2mks)
21. State three structural differences between arteries and veins. (3 mks)
22. What is the function of the following structure in the human reproductive organ?
    1. Fallopian tubes. (1 mk)
    2. Epididymis. (1 mk)
    3. Scrotal sac (1mk)
23.                    
    1. State two ideas proposed by Lamarck’s in his theory of evolution. (2 mks)
    2. Why is Larmark’s theory not acceptable? (1 mrk)