Form 2 Biology Complete Notes (High School Full Notes)

BIOLOGY FORM 2 NOTES COMPLETE FORM 2 BIOLOGY REVISION KIT1 TRANSPORT IN PLANTS AND ANIMALS. Introduction Transport is the movement of substances within an organism. All living cells require oxygen and food for various metabolic processes. These substances must be transported to the cells. Metabolic processes in the cells produce excretory products which should be eliminated before they accumulate. The excretory products should be transported to sites of excretion. Organisms like amoeba are unicellular. They have a large surface area to volume ratio. The body is in contact with the environment. Diffusion is adequate to transport substances across the cell membrane and within the organism. Large multi-cellular organisms have complex structure where cells are far from each other hence diffusion alone cannot meet the demand for supply and removal of substances. Therefore an elaborate transport system is necessary. Transport in plants Simple plants such as mosses and liverworts lack specialized transport system. Higher plants have specialized transport systems known as the vascular bundle. Xylem transports water and mineral salts . Phloem transports dissolved food substances like sugars. Internal structure of roots and root hairs The main functions of roots are ; Anchorage absorption. storage gaseous exchange. The outermost layer in