Explain in an essay how the food chain works?

A food chain describes how energy and nutrients move through an ecosystem. At the basic level there are plants that produce the energy, then it moves up to higher-level organisms like herbivores. ... In the food chain, energy is transferred from one living organism through another in the form of food.  In ecology, a food chain is a series of organisms that eat one another so that energy and nutrients flow from one to the next. For example, if you had a hamburger for lunch, you might be part of a food chain that looks like this: grass rightarrow→right arrow cow rightarrow→right arrow human. But what if you had lettuce on your hamburger? In that case, you're also part of a food chain that looks like this: lettuce rightarrow→right arrow human

Explanation:

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

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