Download kakamega south cemtral districts mock examination

231/1
BIOLOGY
PAPER 1
JULY/August 2014
Marking scheme:
NOTE: Semi colon(;)represents 1 mark
1.
Contain lytic enzymes; that breaks down foreign materials; which can be ingested instead of food.
2.
Absorbs latent heat of vaporization;
3.
(ii)
4.
5.
6.
7.
8.
9.
(i) Juvenile hormone
- Controls metamorphosis in young insects;
Abscic acid
Formation of Abscission layer in leaves and
fruits;
Lactic Acid; Energy;
Allow for impulse transmission from one nerve cell to another;
Presence of Rhizoid; Lack of vascular tissue;
Production of low urine volume;
Production of concentrated/hypertonic urine;
Peristalysis;
Churning of food;
Grass increases;
Black birds decreases;
10.
11.
12.
a) A-Thick iner wall; Rej ; inner wall B-Thin outer wall; Re ; outer wall
b) Regulate the openings and closing of the stoma;;
a) Light - Activates germination hormones;
- Raises internal temperatures of the seed; Award for one
b) Soaking in water - softens seedcoat;
Autotrophs are organisms who utilize simple substances to manufacture complex organic
substances; while Heterotrophs are organisms who depend on complex synthesized organic
substances;
13.
a) Gill;
b) Creates a large surface area for maximum gaseous exchange;
14.
15.
16.
a) Meiosis is a type of cell division where a single parent cell divides to form four haploid
daughter cells; while mitosis is a type of cell division where a single parent cell divides to form two
diploid daughter cells;
b) Lead to formation of haploid gamete cells who through fussion maintains the diploid state of
species;
-May lead to variation due to crossing over;
(Max = lmk)
Uric acid;
Diffusion;
Active transport;
17.
a) Structures who with time get reduced and becomes functionless;
b) - Appendix
- human tail Human hair
(max = 2mks)
18. G
- Sunken stomata;
- Reduced leaf size; needle like
- Succulent leaf and stem
(max = 3mks)
19.
a) A- white matter;
D- grey matter;
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b) Celebral spinal fluid;
20.
a) X- white blood cell / leucocyte; Reject - white cell
Ace -neutrophil
Y- Red blood cell / erythrocyte ; Reject red cell
b) Large lobbed nucleus ; (reject - germs)
21
. it mutates and develops resistance to drugs;
- Multiplies rapidly in red blood cells;
- Cannot be digested by enzymes in the vector;
22.
-High chances of survival due to zygote being highly protected in the body;
- High chances of fertilization
23.
a) It is a cross between parents of unknown genotypes of a dominant trait with a homozygous
recessive trait;
b) Chromosomes of same size which carry similar genes of same number;
24.
a) M-triceps; N-Biseps;
b) M-Contracts; N- Relaxes;
25.
26.
Florigen;
a) Catalyses the break down of toxic hydrogen peroxide; to harmless water and oxygen in
active tissues;
b) Low temperature;
27.
a) Thick cuticle reduces cuticular transpiration;
Thin cuticle increases cuticular transpiration;
b)
Many stomata creates a large surface area for maximum water loss;
Fewer stomata creates a small surface area for minimal water loss;
28.
a) Ability of the eye to bring into sharp focus distant and near objects;
b) Radial muscule relax; and circular muscle contract; to reduce the size of the pupil;
29
a)
T–A–A–G–C–T;
30.
b)
a)
U – A – A – G – C – U;
Co-dominance;
31.
b)
Bb;
- Active transport;
- Cytoplasmic streaming;
32.
a)
Area =
b)
= 125714.29 um;
Area
No of cells = size of 1 cell
22
x 20002;
7
1257114.29
;
5
Reject if no formula.
= 25142.858 Nm;
33.
- Vasoconstriction;
- Hair is raised / erects / constriction of erector pilli muscle;
- Sweat secretion is stopped.
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