Name the following.
(i) The process in plants that links light energy with chemical energy.
(ii) Organisms that can prepare their own food.
(iii) The cell organelle where photosynthesis occurs.
(iv) Cells that surround a stomatal pore.
(v) Organisms that cannot prepare their own food.
(vi) An enzyme secreted from gastric glands in stomach that acts on proteins.
(i) Photosynthesis It is a process by which green plants having chlorophyll synthesise simple sugar (glucose) from water and $CO_{2}$ using the energy of sunlight. The light energy is used in splitting of water molecules into hydrogen and oxygen (i.e. chemical energy).
(ii) Autotrophs Those organisms which can makp their own food from inorganic substances present in the environment are called autotrophs, e.g. green plants, autotrophic bacteria etc.
(iii) Chloroplasts Chlorophyll is the green pigment capable of trapping light energy, required for photosynthesis. This pigment is present in chloroplast present in the leaves.
(iv) Guard cells Each stomatal pore is sorrounded by a pair of guard cells, that control their opening and closing by .the inflow and outflow of water.
(v) Heterotrophs Those organisms which cannot make their own food from inorganic substances and depend on other organisms for their food are called heterotrophs, e.g. all animals, yeast etc.
(vi) Pepsin It is a protein digesting enzyme secreted from gastric glands present in the wall of the stomach.