Biology: A Guide to the Natural World with mybiology" (4th Edition)

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BIOL Study Guide Test 4 Chapter 18: Binomial Nomenclature – The fact that there are two parts to scientific names. Systematics – A field of biology that is concerned with the diversity and relatedness of organisms; part of what systematists do is try to establish the truth about who is more closely related to whom. Phylogeny – Each hypothesis about evolutionary relationships. Homologies – Common structures in different species that result from a shared ancestry. Analogy – A feature in different organisms that is the same in function and superficial appearance. Analogous features have nothing to do with common decent; they merely show that the same kinds of environmental pressures lead to the same kinds of design. Convergent Evolution –When nature has shaped two separate evolutionary lines in analogous ways. (e.g. the litoptern and the horse) Cladistics – A method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants (and nothing else). For example, birds, dinosaurs, crocodiles, and all descendants (living or extinct) of their most recent common ancestor form a clade. It is concerned solely with establishing lines of descent. Cladogram – An evolutionary tree constructed within the cladistic system. Ancestral Characters – Those that existed in an ancestor common to them all Derived Character – A character unique to taxa descended from a common ancestor. Chapter 19: Cretaceous Extinction – the most famous extinction event, which occurred between the Cretaceous and Tertiary periods; this extinction was aided by the impact of a giant asteroid that brought about the end of the dinosaurs. Permian Extinction – The greatest extinction event of all; occurred in the boundary between the Permian and Triassic periods. Accretion – The process by which the Earth was formed; ever-larger particles clumped together: cosmic dust to gravel, gravel to larger balls, larger balls to objects the size of tiny planets. RNA (ribonucleic acid) – In early life-forms, a single molecule performed both the DNA and enzyme roles, allowing for reproduction. The RNA world – Period when early life-forms reproduction was carried out by RNA. Ribozymes – Enzymes composed of RNA instead of protein. These can encode info and act as enzymes. Prokaryotes – Single celled, without nucleus: archaea and bacteria Eukaryotes – All organisms within Domain Eukarya; these have nucleated cells. Cyanobacteria – First organisms to produce oxygen as a by-product of photosynthesis – from particular kind of photosynthesis beginning in the Precambrian. Cambrian Explosion – An alleged sudden appearance of the ancestors of modern animals beginning about 542 Mya Phylum – A group of organisms that share the same body plan Bryophytes –The most primitive land plants that are still with us, represented by today’s mosses, had no vascular structure—meaning a system of tubes that transports water and nutrients.
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Bio Test 4 SG - BIOL Study Guide Test 4 Chapter 18:...

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