click below
click below
Normal Size Small Size show me how
Lecture 1
General Themes
| Term | Definition |
|---|---|
| Levels of organization | molecules, cells, groups of cells, organism, population, community, ecosystem, biosphere |
| The cell is the basic _____, while the organism is the _____. | unit of life; "living thing" |
| The _____ is the most highly integrated biological entity. | organism |
| Animals are complex, multicellular organism that have an _____. | organized structure ("body plan") |
| Reductionism | explanation of biological phenomena from physical and chemical principles; emphasis on lower levels of organization |
| Synthesis | analysis of whole system properties; emphasis on interactions of components at higher levels of organization |
| Emergent properties | new properties that arise at higher levels of organization; result from increased complexity and interactions among parts |
| Proximate causation | biological function depends on structure and physical/biological interactions among components |
| Ultimate causation | biological structures (which result from expression of specific genes) are shaped by evolution; structures have evolved to meet functional needs of organisms |
| Claude Bernard (19th century physiologist) | organism and environment are an interacting system; the internal environment of the organism is regulated to maintain suitable conditions for life in the face of fluctuations in the external environment |
| Homeostasis (Walter Cannon) | relative constancy of the internal environment |
| steady state | input = output; not equilibrium; requires continuous input of energy and molecular materials |
| Adaptation | Characteristic of an organism that enhances survival and reproduction in its specific environment; evolutionary "fit" of animo form and function to its environment |
| Quote by G. Bartholomew | "Natural selection yields adequacy of adaptation rather than perfection." |
| Evolution | the central organizing principle of biology |
| Charles Darwin published _____. | On the Origin of Species by Means of Natural Selection (1859) |
| Evolutionary process | On the Origin of Species by Means of Natural Selection (1859) |
| Evolutionary history | origin and and ancestry of species; all life is related, and all species have descended from common ancestors |
| "Tree of life" | shows current understanding of relationships among species and higher taxa |
| Example of proximate causation | Nerve impulses are caused by a rapid inflow of sodium ions into the nerve cell through protein channels in the cell membrane. |
| Example of ultimate causation | The kangaroo rat has evolved the ability to form very concentrated urine in response to pressure by natural selection to survive in its arid environment. |