Cytology.ٕ√ (1mk).

A father can only transmits the Y- chromosome to the son,√ while haemophilia gene is only found on the X-chromosome.√

It has a large surface area to volume ratio;√gaseous exchange occurs through its body/cytoplasm by diffusion.√

i. Golgi bodies.

ii. Ribosomes.

iii. Lysosome. (3mks)

a) Pedicel/flower stalk;

b) Produce male gametes/pollen grains;

c) Inferior/epigynous;

d) Other floral parts arise above it; (4 mks)

Pay oxygen debt/supply more oxygen; to break down lactic acid; to produce more energy; increase elimination of carbon (IV) oxide. (3mks).

Circular muscles of iris contracts radial muscles relax; ciliary muscles relax increasing tension on the suspensory ligaments; lens becomes thinner increasing the focal lenghth; image focused onto retina.

(a) Investigate whether CO2 is necessary for photosynthesis.

(b) The leaf continues to get water and minimal from the plant.

(c) NaOH absorbs CO2. (d) To decolourise chlorophyll pigments on the leaf.

(a) Insecta;

(b) Mammalia;

(a) K-Facet for articulation with next vertebra;

L-Transverse process for attachment of muscles;

(b) Cervical/Neck region.

(i) More filtration.

(ii) Less reabsorption hence water is passed out in urine.

(iii) Fresh water

(a) Abscisic acid.

(b) -Plumule;

-Cotyledon/cotyledons.

(a)

(i) Resolution. -The ability of a microscope to distinguish as separate structures or entities, objects which otherwise lie close to each other. (ii) The circular area seen through the light microscope;

(b) The specimen must be dead because it’s viewed in a vacuum.

(a) A-Increased in size. B-Reduced in size.

(b)The strip have their cell saps being hypertonic to the sugar solution, √hence takes in water by osmosis,√ their cells become turgid making strips to enlarge.√

-Thin epithelium/one

-cell thick.

-Highly vascularised to,

(a) Ascaris. Tegetes.

(b) -Can interbreed freely to produce viable offprings.

-Have the same number of chromosome in the cells.

(i) The kidney tubules becomes less becomes less permeable to water hence reabsorbing less water into the blood stream. This leads to production of a lot of dilute urine.

(ii) Diabetes insipidus.

a) -Protects the eggs against mechanical damage/invasion by pathogens/wide temperature fluctuations.

-Its distasteful to some predators thus it prevents the predators from eating them.

-It anchors the eggs into the substratum e.g. water plant, hence preventing the eggs from swept away by water.

-Eggs are evenly spread within the jelly ensuring that each egg has adequate supply of air. (Any 2 mks)

(b)The a crosome bursts open; releasing lytic enzyme that dissolve the egg membrane; a crosome turns inside out forming a sharp fine filament; which enables the sperm head penetrate the eggs/ovum for fertilization;(Max 2)

Entamoeba histolytica.

Mycobacterium tuberculosis.

The higher the saturation deficit, the greater the rate of transpiration; the lower the saturation deficit the lower the rate of transpiration. a

(a)45.5-7.5=38.0√ 1 ± 0.5

(b)-Excessive growth of algae/Eutrophication.√depletes dissolved oxygen hence leads fish suffocating.√ (Any one)

-Excessive application of inorganic fertilizer /nitrate fertilizer.

-Sewage. (Any one)

(i)Ball and socket(joint)

(ii)Hinge (joint).

(a) 3-Incus;rej ear ossicles. 4-Auditory nerve.

(b) 5-Cushions excessive vibrations. 7

-Contain sensory cells when stimulated generates nerve impulses to the brain for interpretation/ integration.