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Marking scheme biology paper one Sukemo joint 2016
1(a) bacteriology; virology; mycology; parasitology ;acc; any two;
(2mks)
(b) Evolution;
(1mk)
2. (a)environmental pollution; food shortage;
(b) Do not destroy the habitat of the organism;
(1mk)
(2mks)
Do not harm the organism;
For live specimens after study return to their habitats;
3 (i) it is an offspring of two organisms, which belong to different species
(ii)Algae; protozoans acc; specific examples like Plasmodium, Paramecium
(1mk)
(2mks)
4. (a)(i) it is in aperture that regulates/ controls the amount of light passing through the condenser to
the specimen on the stage.
(ii) It magnifies both dead and live specimens
(b) It increases the surface area for the action of enzymes in respiration/ enzyme
attachment/respiration
(1mk)
(1mk)
5.Plant cells lose water through transpiration; turgor in cells is reduced, the turgor in cells is reduced,
the whole cell shrinks and the plant droops;
(2mks)
6. A- Water;
(3mks)
B- Hydrolysis;
C- Glucose;
(b) Glucose is soluble; easily absorbable; easily oxidized to give energy;
7. (a) (i)the cells take in water; and expand;
(ii) Auxins ;
(2mks)
(2mks)
(1mk)
8. (a)natural/innate immunity is transmitted from parents to offsprings while acquired immunity is got
after one suffers from a disease or through vaccination;
(2mks)
(b) (i)blood group O can only receive blood from O alone;
(1mk)
(ii) When blood vessel is injured, platelets are exposed to air rapture on damaged tissues to
release thromboplastin/ thrombokinase; thromboplastin neutralizes heparin (anticlotting factor);
activates prothrombin to thrombin; thrombin activates conversion of fibrinogen to fibrin clot; (4mks)
9. (a) tracheole
(1mk)
(b) tracheole has a thin film of moisture to dissolve the respiratory gases/ for gases to dissolve in
solution form;
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Tracheole is one cell thick to reduce the distance of diffusion of respiratory gases/ for respiratory gases
to diffuse through a shorter distance;
rej; they are numerous
(1mk)
(c ) epithelial layer with ciliated cells had been destroyed; no trapping of particles;
10. (a) glucose + oxygen
carbon(IV) oxide + water + energy
C6H12O6 + 6O2
(2mks)
(1mk)
6CO2 +6H2O + 2880Kj;must be balanced;
(b) Adenosine diphosphate combines with a phosphate and 34kJ of energy; to form adenosine
triphosphate/ATP;
(2mks)
(c ) carbon (IV) oxide; water; energy (ATP)
11. (a)excess water;
(b) (i)blood capillaries; erector pili muscles and hair; sweat glands;
(ii) Sweat glands; blood capillaries;
(c ) seals live in cold environments. Fatty tissue act as an insulator; to prevent excessive heat loss
from their bodies;
(2mks)
12.(a)(i)killing the vector at one stage of its life cycle;/
(1mk)
Killing the pathogen while it is inside the body of the body of the second host like;/
Preventing the pathogen from developing in the host by treatment such us by use of drugs;/
(ii) Protozoa
(1mk)
(b) Supply of oxygen; source of food; remove CO2; provide shelter; provide breeding sites;
1st two;
(c ) (i) grass;/ tree;
(2mks)
(1mk)
(ii) Some are lost through excretion; and respiration;
13. (a) light penetration in water;
(1mk)
(2mks)
(b) Light intensity
14. (a) the ovum has a short lifespan of about 24 hours; to enable proper implantation; (2mks)
(b)one male gamete nucleus fuses with the functional egg cell; to form a diploid zygote; the other
male nucleus fuses with both polar nuclei to form a triploid nucleus(primary endosperm nucleus);
(3mks)
15.(a) M- Acetabulum; N- Obturator foramen;
check spellings;
(b) Can expand to allow widening of the pelvic girdle;
16. short/reduced neural spine;
The sukemo joint evaluation mock 2016 © 2016
(2mks)
(1mk)
(3mks)
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Reduced centrum;
Presence of vertebraterial canal;
Divided transverse processes;
Wide neural canal;
17. Cardiac muscle fibre are uninucleated while skeletal muscle fibre is multinucleated;mark at the end;
A skeletal muscle is made up of a bundle of long fibres running the whole length of the muscle while
cardiac muscle consists of short cells thickened with intercalated discs;;
Skeletal muscle cells fatigue rapidly while cardiac muscle cells do not fatigue;;
(2mks)
18.Increased length of productive season; higher yields; ease of harvesting as in coconut as dwarf
varieties are produced; flowers such as roses, orchids are selectively bred for their color, shape and
aroma; adaptations to local conditions;
acc; the 1st 3;
(3mks)
19.(a)the pupil becomes smaller; to prevent damage of retina by excessive light; (2mks)
(b)(i)
(2mks)
NB; concave lens; image on the retina
20.Protection of the inner delicate parts of the flowers;
Reduction in transpiration;
Regulation of temperature;
Enables the plants to obtain some limited mineral nutrients/feeding in insectivorous plants;
(2mks)
21.(a) emphasizes that acquired characteristics of organisms in the course of their life time are
transmitted to their offsprings;
(1mk)
(b) Similarity in bone structure; comparative anatomy; comparative embryology;
22 (a) juvenile hormone; corpus allatum;
rej; corpora allata
(b) Intermittent growth;
(1mk)
(1mk)
(1mk)
Total 80mks
The sukemo joint evaluation mock 2016 © 2016