| A | B |
|---|
| metabolism | all the chemical reactions occurring in an organism |
| metabolism | food provides energy & matter that cells use for energy & chemical building blocks |
| growth and development | after an organism first forms, it increases in size & undergoes maturation |
| growth and development | changes in cells as they age, as directed by their genetic code |
| homeostasis | cells must maintain near constant internal physical and chemical conditions in order to function correctly |
| homeostasis | for example, cells maintain stable internal pH, temperature, ion, and molecule concentrations |
| universal genetic code | all cells contain DNA that controls their traits |
| universal genetic code | DNA in cells allows them to adapt and evolve, as well as to reproduce |
| adapt and evolve | individuals of a species have some variation in their traits; some variations increase survival & reproduction |
| adapt and evolve | genetic (inherited) traits that increase survival & reproduction become more common as generations pass |
| respond to stimuli | cells change their activity in response to messages from other cells |
| respond to stimuli | cells change their activity when conditions change, allowing them to maintain homeostasis |
| body made of cells | unicellular organisms, like prokaryotes & protists, have a microscopic body made of only one cell |
| body made of cells | multicellular organisms have bodies containing many cooperating, interdependent cells |
| reproduction | if asexual, one parent generates genetically identical offspring |
| reproduction | if sexual, two parents generate genetically diverse offspring, all having half of their DNA from each parent |
