a) Name two functional parts of the mammalian circulatory system. (2 marks) b) Name two diseases of the mammalian circulatory system. (2 marks) c) Describe water movement from the soil into a plant until it is lost to atmosphere through the leaf. (16 marks)

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a) Heart; blood capillaries;
b) Varicose veins; thrombosis; arteriosclerosis;
hypertension; First two
c) Water is absorbed into the root hairs by osmosis; root hairs cell sap is hypertonic to the surrounding film of water; Root hair sap become dilute compared to adjacent cortex cells; hence set .osmotic pressure for water to move by osmosis; some water moves by cytoplasmic streaming; up to the endodermis; water then moves across the endodermis by active transport; to the root xylem; water xylem move to the plant by root pressure; capillarity; aadhesive and cohesive forces; and transpiration pull;
The water then enters leaf cells by osmosis; then into the intercellular air spaces; of the spongy mesophyll layer; after is then lost to atmosphere by diffusion; through stoma; process called transpiration;

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