LIFE SCIENCE

Detailed explanation-1: -Energy enters all ecosystems from the sun or from inorganic chemicals. The energy then flows through ecosystems from producers, who can use inorganic forms of energy, to consumers, who can obtain energy only from organic compounds in other living things.

Detailed explanation-2: -Energy flows through an ecosystem in one direction, from the sun, or inorganic compounds, to autotrophs and then, to various heterotrophs. This energy is passed along in a series of steps in which organisms eat or are eaten. This is called a food chain.

Detailed explanation-3: -Primary producers use energy from the sun to produce their own food in the form of glucose, and then primary producers are eaten by primary consumers who are in turn eaten by secondary consumers, and so on, so that energy flows from one trophic level, or level of the food chain, to the next.

Detailed explanation-4: -Most autotrophs use a process called photosynthesis to make their food. In photosynthesis, autotrophs use energy from the sun to convert water from the soil and carbon dioxide from the air into a nutrient called glucose. Glucose is a type of sugar. The glucose gives plants energy.