| A | B |
|---|
| organism | A living thing. |
| cell | The basic unit of structure and function in living things. |
| unicellular | A type of organism that is made up of a single cell. |
| multicellular | A type of organism that is made up of many cells. |
| development | The process of change that occurs during an organism’s life to produce a more complex organism. |
| stimulus | A change in an organism’s surroundings that causes the organism to react. |
| response | An action or change in behavior that occurs as a result of a stimulus. |
| reproduce | The production of offspring that are similar to the parents. |
| spontaneous generation | The mistaken idea that living things arise from nonliving sources. |
| controlled experiment | An experiment in which all of the variables except for one remain the same. |
| manipulated variable | The one factor that a scientist changes to test a hypothesis during an experiment; also called the independent variable. |
| autotroph | An organism that makes its own food. |
| heterotroph | An organism that cannot make its own food. |
| homeostasis | The process by which an organism’s internal environment is kept stable in spite of changes in the external environment. |
