How do cells, tissues, organs, and organ systems work
together in a multicellular organism?

Key points. Humans—and other complex multicellular organisms—have systems of organs that work together, carrying out processes that keep us alive. ... Cells make up tissues, tissues make up organs, and organs make up organ systems. The function of an organ system depends on the integrated activity of its organs.

Explanation:

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

the answer is a) cell division.

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