BSC 160 Lecture Notes - Lecture 2: Hospital-Acquired Infection, Endospore, Gamma Ray
Document Summary
Ecology: the study of relationships between organisms and with their environment. Population: organisms of the same type in one specific location. Community: all organisms in a given area. Ecosystem: the communities and their abiotic environment: also called a biome, includes oceans, rivers, deserts, arctic tundra, etc. Biosphere: everything, a variety of species; biomass. Living organisms interact with each other; they do not live in isolation: three primary relationships between organisms exist: Commensal: one party benefits, the other has no change. Parasitic: one party benefits, the other is physically harmed. Microenvironment: portion of the environment immediately surrounding the organism: most relevant at cellular level, hard to measure. Macroenvironment: all other influences on the organism: easy to measure, biofilms are macroenvironments. Trophic levels: who eats who? regarding food source: exist in a generality of three levels. Primary producers: who we count on to start everything off: autotrophs, photoautotrophs, chemolithoautotrophs, etc, use carbon dioxide, microbes themselves photosynthesize more than photoautotrophs.