Biology Paper 1 Questions and Answers - Kakamega Evaluation Mock Exams 2022

QUESTIONS

1. Name the antigens present in red blood cells of a person whose blood group is B positive. (2mks)
2. Give reasons for the following structural modifications in axial skeleton of humans
   1. Fused sacral vertebrae (1mk)
   2. Long transverse process in lumbar vertebrae. (1mk)
3.    
   1. What is adaptive radiation? (1mk)
   2. State two ways in which Homo sapiens differs from Homo habilis (2mks)
4. State three characteristics of class Reptilia. (3mks)
5. The diagram below represents the structure of a yeast cell as seen under a light microscope.
   
   Name parts labeled L & K(2mks)
6. Which part of plant normally shows
   1. Increased growth at lower auxin concentration (1mk)
   2. Decreased growth at lower auxin concentration (1mk)
7. State the functions of the following parts of a light microscope.
   1. Fine adjustment knob (1mk)
   2. Condenser (1mk)
8. Give a reason for the following features present in human trachea
   1. Ring of cartilage (1mk)
   2. Presence of cilia (1mk)
9. The diagram below shows a plant supportive tissue
   
   
   1. Identify the tissue (1mk)
   2. State two similarities between tissue named in 9(a) above and one conducting water in dicotyledonous plants
10. A wild beast in Masai Mara  National Park was found to be infested with a lot of ticks. State the trophic level occupied by the following organisms:
    1.    
       1. Wild beast (1mk)
       2. Ticks (1mk)
    2. Sketch a pyramid of numbers to represent above feeding relationship. (1mk)
11.        
    1. Name the causative agent of the following diseases in humans.
       1. Bilharziasis (1mk)
       2. Syphillis (1mk)
    2. Describe the following defects:
       1. Varicose veins (1mk)
       2. Thrombosis (1mk)
12. The flow chart below shows the movement and fate of carbohydrate synthesized by green plants.
    
    
    1. Name the type of carbohydrate that is
       1. Transported from leaf to other parts of plant (1mk)
       2. Found in storage tissues (1mk)
    2. Name two main photosynthetic tissues found in a leaf (2mks)
13. State the roles of the following cell organelles in a cell
    1. Lysosomes (2mks)
    2. Centrioles (1mk)
14. Name the physiological process involve in the movement of the following substances in and out of the cell.
    1. Mineral salts (1mk)
    2. Water (1mk)
15. Below is the dental formula of an organism
    i³/₃   C¹/₁    Pm⁴/₄    m²/₃
    
    1. Calculate the total number of teeth in the jaw of the animal (2mks)
    2. With a reason, identify the type of dentition for the organism (2mks)
16. The diagram below shows a section through a plant organ
    
    
    1. Name the class of the plant from which the section was obtained (1mk)
    2. Give a reason for your answer in a(i) above (1mk)
17.      
    1. Name two structures for gaseous exchange in aquatic plants. (2mks)
    2. State one adaption of the above named structures. (1mk)
18. During a biological trip, plants that had flowers drew the attention of students
    1. Name the subdivision of the plants (1mk)
    2. Name two possible characteristics that students would use to conclude that they were insect pollinated. (2mks)
19. Define the following terms
    1. Homologous structures (1mk)
    2. Vestigial structures (1mk)
20. Name the type of responses exhibited by the following 
    1. Pollen tube growth towards the embryo sac (1mk)
    2. Maggot moving from the lit part of boiling tube to the part painted black (1mk)
    3. Folding of the leaves of the Mimosa Pudica plant on touch (1mk)
21. Insulin is a hormone synthesized using bacteria DNA. It is possible to obtain from hospitals because of the new technology
    1. Name the technology used in the case above. (1mk)
    2. Why were bacteria preferred in the medicine production (2mks
22.    
    1. State the role of the following parts of ear in the hearing process
       1. Ear drum (1mk)
       2. Cochlea (1mk)
    2. Explain why the body temperature of a healthy human being may rise up to 390C on a hot humid day. (3mks)
23. Explain what happens to human body when glucose level is above normal (3mks)
24. Name three mechanisms that ensure cross pollination takes place in flowering plants. (3mks)
25. State the functional difference between sensory and motor neurons (1mk)
26. Give two reasons why class insecta is the most numerous among members of phylum arthropoda. (2mks)
27. The diagram below shows the appearance of a plant cell after it had been placed in a strong salt solution
    
    
    1. Name the process that occurred in the cell shown above. (1mk)
    2.    
       1. Which substance is present in the regions marked 1? (1mk)
       2. Give reasons for your answer in b(i) above (2mks)
28. State two roles of a fruit to a plant (2mks)
29. What is the importance of the following in an ecosystem?
    1. Bacteria and fungi (1mk)
    2. Predators (1mk)
30. Outline three roles of active transport in the human body. (3mks)

MARKING SCHEME

1. Antigen B; rej. Small b
   Antigen Rhesus; (1mk)
2.       
   1. for support / to transmit weight of stationery animal to the rest of body; (1mk)
   2. To increase surface area for attachment of large abdominal of muscles (to maintain posture and flex spine); (1mk)
3.         
   1. Situation where organisms have homologous structures / structures with common embryonic origin but modified to perform different functions; to adapt organisms to different functions; to adapt organisms to different habitats / niches; (1mk)
   2. Standing upright / erect posture ; high intellectual capacity / thinking capacity hig; communicate through speech / language; acc correct comparison (2mks)
4.      
   • Body covered with dry scaly skin;
   • Majority have four limbs with snakes having no limb
   • Eggs have leathery shell (to reduce desiccation)
   • Have lungs for gaseous exchange 
   • Heart is three chambered two atric and partially divided ventricle or four chambered; (3mks)
5. L – Glycogen granule; rej Plural
   K – Vacuole; (2mks)
6.    
   1. Root; (1mk)
   2. Shoot;  (1mk) 
7.      
   1. Moves the body through small distances to bring image / specimen / object into sharper focus;
   2. Concentrates light (from mirrow) into object on stage; (2mks)
8.      
   1. to keep it open / provide mechanical strength
   2. to propel dust / bacteria / mucus out of trachea. (2mks)
9.       
   1. Trachaid?
   2. thickened with lignin;
      Has tapered ends (tracheids); (3mks)
10.      
    1.      
       1. Primary consumer;
       2. Secondary consumer; (2mks)
    2.   
       
11.        
    1.      
       1. Schistosoma mansoni;
       2. Treponema pallidum; (2mks)
    2.    
       1. Swellings in veins due to weakened / defective valves resulting into accumulation of blood;
       2. Formation of (a blood) clot in the blood vessels; (2mks)
12.      
    1.      
       1. Sucrose ; (2mks)
       2. Starch;
    2. Pollisade;
       Spongy; (2mks)
13.      
    1. Burst / break drum to release lytic enzyme; to digest dead and worm out cell organelles;
    2. Form spindle during cell division/ formation of cilia and flagella; (1mk)
14.      
    1. Active transport / Diffusion; (1mk)
    2. Osmosis ;(1mk)
15.          
    1. 10 x 2 = 20 ; 
       11 x 2 = 22
       = 42 teeth; (2mks)
    2. Heterodont;
       Reason – Has different types of teeth; OWTTE.
16.      
    1. Dicotyledonae; rej wrong spelling Dicot, dicotyledonae
    2. Vascular bundles arranged in (concentric) ring around the pith; presence of pith; (1mk)
17.      
    1. Aerenchyma (tissue);  (2mks)
       Pneumatophores; rej breathing roots
    2. Have large air spaces for circulation of air / gaseous exchange; (1mk)
18.        
    1. Spermatophyte
    2. brightly coloured petals scented nectar guides
19.      
    1. Structures from the same (embryonic) origin / ancestry but modified to perform different functions; (1mk)
    2. Structures that have ceased to function over long period of time hence become reduced in size; (1mk)
20.      
    1. Chemotropism
    2. (Negative) photo taxis;
    3. Haptonasty / Thigmonasty;
21.      
    1. Genetic engineering;
    2. Reproduce of very fast; hence producing more lormures;
22.      
    1.      
       1. Currents sound waves to sound vibrations; transmit sound vibrations to ear obscicles;
       2. Currents vibrations into impulses (for hearing)
    2. More sweat produced; but does not evaporate; due to humid conditions, hence more leaf retained;
23. Pancreas secreted insulin hormone; hormone activates liver cells; to convert excess glucose to glycogen fats / increase in the rate of metabolism to break down glucose into energy; (3mks)
24.      
    • Protogyny and protandry (3mks)
    • Self sterility / incompatibility
    • dioecious plant where distillate and staminate flower are born on different plants.
25. Sensory neuron - Transmit impulses from receptors to CNS
    Motor neuron - Transmit impulses from CNS to effectors; (1mk)
26.      
    • Ability to fly;
    • Can inhabit most types of habitats;
    • Have varied mouth past for feeding 
27.      
    1. Plasmolysis (1mk)
    2.    
       1. Strong salt solution; (1mk)
       2. The salt solution passed through the cell wall because it is fully permeable; but cannot pass through the cell membrane which is semi permeable; (2mks)
28. Protect the seeds; As a storage organ; Aids in seed dispersal; Max (2mks)
29.      
    1. Decomposition / recycling of nutrients; 
    2. requlate population of he prey / herbivores; (1mk)
30.      
    • Reabsorption of salt and sugar in kidney nephrons;
    • Absorption of digested food;
    • Excretion of waste products from body cells
    • Sodium pump in the nervous system