BIOL 115 Lecture Notes - Lecture 1: Homeostasis, Eukaryote, Plant
Document Summary
Cell smallest structural and function unit of an organism: some organisms are single-celled; some like humans, are multicellular (composed of many cells). Tissue group of similar cells that perform a particular function. Organ system group of organs that work together for a common purpose. Population the members of one species in a particular area. Ecosystem community of populations interacting with the physical environment. Humans acquire materials and energy by eating. Food provides nutrients, which are used for building blocks and energy. Metabolism all of the chemical reactions that occur within cells. The ultimate source of energy for life on earth is the sun. Photosynthesis used by plants, algae, and some bacteria. Harvests energy from the sun and converts it to chemical energy. Produces sugar, which serve as the basis for the food chain for other organisms. Homeostasis a constant internal environment: most organ systems strive to main homeostasis, that is, body temperature is maintained within a narrow range of values.
