Fill in the blanks with the most suitable word

A food chain is the way energy goes from one living thing to another through food. Plants are the first (26) _______ in most food chains. Plants use the energy in sunlight to make their own food. Plants store the energy in their leaves and stems. Plants are called primary producers in food chains. Animals eat the plants (27) _______ use the Sun's energy to grow. Animals are called (28) _______. Animals that eat plants are primary consumers. Animals that eat other animals are secondary consumers. Animals store the energy in their bodies. Energy flows (29) _______ plants and bigger animals through the steps of eating and being eaten. Each part of the food chain is directly connected to the other, just (30) _______ the links in a chain.