| A | B |
|---|
| organism | living things |
| cell | basic unit of structure and function in all organisms |
| unicellular | single celled organisms like bacteria |
| multicellular | many celled organisms like humans |
| metabolism | chemical reactions through which an organism builds up or breaks down materials |
| stimulus | a change in an organism's surroundings that cause it to react, such as light or sound |
| response | an action or a change in behavior |
| development | the process of change that occurs during an organism's life |
| asexual reproduction | one parent that produces offspring identical to itself |
| sexual reproduction | two parents that produce offspring that combines the genetic material from both parents |
| spontaneous generation | the mistaken idea that living things can arise from nonliving sources |
| controlled experiment | when a scientist carries out a series of tests that are identical in every respect except for one factor |
| autotroph | organisms that make their own food |
| heterotroph | organisms that cannot make their own food |
| homeostasis | the maintenance of stable internal conditions such as water intake and body temperature |
