BIOL 121 Lecture : Biology 121
Document Summary
Prokaryotes- diversity of types of nutrition; domain bacteria, domain archea. As humans, we could not communicate without the concept of species. Evolution address basic problems of trying to explain diversity of organisms on earth and how they arose. Evolution is the notion that living things gradually change from one form to another over the course of time. Characteristics of life: life consists of one or more cells. All forms can be divided based on their cell structure. Not all unicellular organisms are bacteria (unicellular algae, protozoa) Membrane bound organelles: life requires a constant input of energy and raw materials, autotrophs- synthesis their own food. Used external energy source to produce organic matter from inorganic raw material. >photoautotrophs- use light from sun and inorganic materials. >chemoautotrophs- use inorganic matter obtained from other organisms: heterotrophs- require preformed organic molecules. Used energy in organic matter obtained from other organisms (eaten)