basic unit of structure and function in living things
the outside boundary of a cell
the control center of a cell that directs the cell's activities and contains the information that determines the cell's form and function
the material within a cell apart from the nucleus
a group of similar cells that perform the same function
a body tissue that contracts or shortens, making body parts move
A body tissue that carries electrical messages back and forth between the brain and every other part of the body.
a body tissue that provides support for the body and connects all of its parts
a body tissue that covers the surfaces of the body, inside and out
a structure in the body that is composed of different kinds of tissue
a group of organs that work together to perform a major function in the body
The process by which an organism's internal environment is kept stable in spite of changes in the external environment.
the reaction of a person's body to potentially threatening, challenging, or disturbing events
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