(i) The leaves of plants contain green pigments called chlorophyll which is necessary for photosynthesis. Plants reflect green light of sunlight, so they look green.
(ii) The skin of earthworm is quite thin and moist and has rich blood supply. So, it respires through its skin. Guard cells
(iii) An organism requires nutrients like carbohydrates, fats, proteins, minerals and vitamins for the growth, reproduction and metabolic activities, so nutrition is necessary for an organism.
(iv) We boil the leaf in alcohol to remove chlorophyll from green leaf.
