Biology Paper 1 Questions and Answers - Mangu High School Mock Exams 2022

QUESTIONS

1. Why is the pancreas considered a dual gland? (2 mks)
2. State the function of cristae in mitochondria. (1 mk)
3. The sketch graph below shows population growth rate of a certain organism
   
   List down four factors that could have caused limited growth at R. (4 mks)
4. Suggest why green plants are included in the fish aquarium. (3 mks)
5. State two observable features that can be used to identify the members of the phylum chordata. (2 mks)
6. Name causative agent for each of the following diseases.
   1. Typhoid (1 mk)
   2. Malaria (1 mk)
7. State three functions of blood other than transport. (3 mks)
8. Give two reasons why lumbar vertebrae have long and broad transverse processes.(2 mks)
9. Give three differences between endocrine system and nervous system. (3 mks) 
   

   Endocrine system	nervous system

10. State three ways in which seed dormancy benefits a plant. (3 mks)
11. Give an example of a sex linked trait in humans on;
    Y chromosome (1 mk)
    X chromosome  (1 mk)
12. Name three gaseous exchange structures in higher plants. (3 mks)
13. Name three features that distinguish man from apes even though they are closely related in evolutionary Tree. (3 mks)
14. Give a reason for the following;
    1. A mature plant cell does not lose its shape even after loosing water. (1 mk)
    2. Xylem vessels do not collapse when they do not contain water. (1 mk)
15. The diagram below represents a nephron of a mammal
    
    
    1. Name the parts marked A and B (2 mks)
    2. Name a major substance in glomerular filtrate whose concentration remains the same between A and C. (1 mk)
16. What is the function of eustachian tube that link the middle ear with the throat. (1 mk)
17. Below is a diagram of a joint in a mammalian skeleton
    
    
    1. Name the type of joint represented by the diagram above. (1 mk)
    2. Identify the part labeled D and E (2 mks)
18. State how the alveolus of the lungs of a mammal is adapted to its function. (3 mks)
19. State the function of cerebrospinal fluid. (2 mks)
20. Explain how water from the soil reaches the xylem vessels of the root. (4 mks)
21. State the functions of the following parts of the human car.
    1. Ear ossicles
    2. Cocclea
22. Name three types of muscles found in human body. (3 mks)
23. Write the type of gene mutation represented by the following analogue.
    1. Intended message: BRING THERMOS ON OUTING 
       Actual message: BRING MOTHERS ON OUTING
       Type.................................................(1 mk)
    2. Intended message PLEASE SAY WHERE YOU ARE 
       Actual message PLEASE STAY WHERE YOU RAE
       Type.................................................(1 mk)
24.  With an aid of diagram distinguish between marginal and parietal placentation in fruits. (2 mks)
    

    Marginal	Parietal

25. Name two raw materials for the process of photosynthesis (2 mks)
26. Giving reasons, identify the mode of feeding of the animal whose dental formula is given below.
    
    Mode of feeding (1 mk)
    Reasons (2 mks)
27. Name three characteristics of wind pollinated flowers. (3 mks)
28. Give two reasons why accumulation of lactic acid during vigorous exercise leads to an increase in heart beat. (2 mks)
29. Explain why sexual reproduction is important in organisms. (2 mks)
30.                    
    1. Name two sources of oil as a water pollutant. (2 mks)
    2. For each of the sources named in (a) above, state one way of controlling it.(2 mks)
31. Name three secondary sexual characteristics that start occurring in human males on the on set of testosterone hormone production. (3 mks)

 MARKING SCHEME

1. Why is the pancreas considered a dual gland? (2 mks)
   It's both endocrine and exocrine
2. State the function of cristae in mitochondria. (1 mk)
   increase surface area for attatchnebt of respiratory enzymes
3. The sketch graph below shows population growth rate of a certain organism
   
   List down four factors that could have caused limited growth at R. (4 mks)
   most cells are differentiated
   rate of cell division equals cell death
   limited food resources
   accumulation of metabolic wastes
   limited space
4. Suggest why green plants are included in the fish aquarium. (3 mks)
   to use carbon (iv) oxide
   provide oxygen
   provide breeding sites
5. State two observable features that can be used to identify the members of the phylum chordata. (2 mks)
   presence of post anal tail
   presence of natochord
6. Name causative agent for each of the following diseases.
   1. Typhoid (1 mk)
      salmonella typhi
   2. Malaria (1 mk)
      plasmodim falciparum
7. State three functions of blood other than transport. (3 mks)
   protection from infections
   blood clotting
   thermoregulation
8. Give two reasons why lumbar vertebrae have long and broad transverse processes.(2 mks)
   increase S.A for attachment of abdominal muscles
   provide support  / withstand weight of abdomen
9. Give three differences between endocrine system and nervous system. (3 mks) 
   

   Endocrine system	nervous system
   use hormones	use nerve impulses
   hormones are carried by blood	impulses are carried by nerve
   slower	faster
   effects long lasting	effects short lived

10. State three ways in which seed dormancy benefits a plant. (3 mks)
    allows time for disposal
    allows maturation of embryo
    enables the plant to survive harsh environments
11. Give an example of a sex linked trait in humans on;
    Y chromosome (1 mk)
    hairy pinna/nose | webbed toes | premature baldness
    X chromosome  (1 mk)
    colour blindness | haemophilia | duchene muscle dystrophy
12. Name three gaseous exchange structures in higher plants. (3 mks)
    stomata
    lenticles
    cuticle
    epidermis
13. Name three features that distinguish man from apes even though they are closely related in evolutionary Tree. (3 mks)
    bipedal gait
    enlarged brain / skull
    smaller lower jaw
    smaller cannines
    non - opposable toe
14. Give a reason for the following;
    1. A mature plant cell does not lose its shape even after loosing water. (1 mk)
       It has a rigid epithelial cell wall
    2. Xylem vessels do not collapse when they do not contain water. (1 mk)
       their walls are ligified
15. The diagram below represents a nephron of a mammal
    
    
    1. Name the parts marked A and B (2 mks)
       A Bownam's capsule
       B descending loop of Heile
    2. Name a major substance in glomerular filtrate whose concentration remains the same between A and C. (1 mk)
       Urea
16. What is the function of eustachian tube that link the middle ear with the throat. (1 mk)
    equilize pressure between the middle and enters the ear (to prevent bursting of the eardrum)
17. Below is a diagram of a joint in a mammalian skeleton
    
    
    1. Name the type of joint represented by the diagram above. (1 mk)
       ball and socket
    2. Identify the part labeled D and E (2 mks)
       D ligament
       E synovial fluid
18. State how the alveolus of the lungs of a mammal is adapted to its function. (3 mks)
    highly vascularized for rapid transport of gases
    moist to dissolve gases
    thin epithelium for rapid diffusion of gases
    large surface area for rapid diffusion of gases
19. State the function of cerebrospinal fluid. (2 mks)
    provide oxygen and nutrients to brain / spinal cord
    absorbs the shock
20. Explain how water from the soil reaches the xylem vessels of the root. (4 mks)
    soil solution is hypotonic to cell sap of root hair cells, water enetrs into root hairs by osmosis; cell sap of root hair between hypotonic to sap of adjacent cortex cells causing them to gain water; this continues until water enters the xylem
21. State the functions of the following parts of the human car.
    1. Ear ossicles
       amplifying sound vibrations
    2. Cocclea
       contains endolymph and perilymph which move sensory hairs
22. Name three types of muscles found in human body. (3 mks)
    cardiac
    smooth
    skeletal
23. Write the type of gene mutation represented by the following analogue.
    1. Intended message: BRING THERMOS ON OUTING 
       Actual message: BRING MOTHERS ON OUTING
       Type....inversion ..(1 mk)
    2. Intended message PLEASE SAY WHERE YOU ARE 
       Actual message PLEASE STAY WHERE YOU RAE
       Type....inversion......(1 mk)
24. With an aid of diagram distinguish between marginal and parietal placentation in fruits. (2 mks)
    
25. Name two raw materials for the process of photosynthesis (2 mks)
    water
    carbon (iv) oxide
26. Giving reasons, identify the mode of feeding of the animal whose dental formula is given below.
    
    Mode of feeding (1 mk)
    herbivourous
    Reasons (2 mks)
    lack of incisors on upper jaw
    lack of canines on both jaws
27. Name three characteristics of wind pollinated flowers. (3 mks)
    large anthers
    small pollen grains
    feathery stigma / sticky stigma
    long fillaments
28. Give two reasons why accumulation of lactic acid during vigorous exercise leads to an increase in heart beat. (2 mks)
    increase supply of oxygen to muscles
    rapid transport of lactic acid to the liver
29. Explain why sexual reproduction is important in organisms. (2 mks)
    it leads to mixing of genetic materials s which cause variations;
30.                    
    1. Name two sources of oil as a water pollutant. (2 mks)
       oil tankers accidents
       damged warships
    2. For each of the sources named in (a) above, state one way of controlling it.(2 mks)
       use pipelines to transport oil
       peaceful esolution of conflicts / cleaning oil spills using bacteria
31. Name three secondary sexual characteristics that start occurring in human males on the on set of testosterone hormone production. (3 mks)
    facial hair / pubic hair
    deepening voice
    enlargement of testes and penis
    increase in masculinity
    broadening of shoulders