Exam 2 | BSCI 103 - WORLD OF BIOLOGY, Quizzes of Biology

Download Exam 2 | BSCI 103 - WORLD OF BIOLOGY and more Quizzes Biology in PDF only on Docsity! TERM 1 Artificial Selection (Chapter 13) DEFINITION 1 Artificial selection (or selective breeding) describes intentional breeding for certain traits, or combination of traits.The term was utilized by Charles Darwin in contrast to natural selection. Examples: The Food we eat Dog Breeding TERM 2 Natural Selection (Chapter 13) DEFINITION 2 *Interaction between organism and the environment. * Only works with heritable traits Members of population differ in traits -All species can produce more offspring than habitat can support- Therefore, there must be competition-Individuals that have superior traits will survive better and leave behind more offspring- Unequal survival will cause favorable traits to accumulate *Natural selection brings about change over long periods of time through minor advantageous changes. TERM 3 Evidence for Evolution (Chapter 13) DEFINITION 3 1.)Fossils 2.)Fossil record preserves the sequence and history of organisms changing 3.).Biogeography- movements and isolation of landmasses 4.)Comparative anatomy -homologous structures those shared by common descent but different due to function 5.)DNA sequences allow us to compare homologous genes between distantly related organisms hox gene-flies and humans TERM 4 Evolutionary trees (Chapter 13) DEFINITION 4 a. Trees are used to represent evolutionary relationship b. Branching points indicate where a new trait arose from a common ancestor, a trait shared by all members of that lineage c. Related members in a branch on an evolutionary tree are called a clade TERM 5 Population (Chapter 13) DEFINITION 5 group of individual living in the same place at same time capable of interbreeding All genes in population make up the gene pool TERM 6 Micro-Evolution (Chapter 13) DEFINITION 6 change in gene frequencies in a population TERM 7 Sources of Genetic Variation (Chapter 13) DEFINITION 7 1.) Mutations-changes in DNA sequences through mechanisms we discussed is the ultimate source of genetic variation 1 in 100,000 genes per generation 2.) Sexual Reproduction TERM 8 Hardy- Weinberg (Chapter 13) DEFINITION 8 equation tells use if population is evolving *Assumptions of Hardy-Weinberg* i. Large population ii. No gene flow between population iii. No mutations iv. Random mating v. No selection TERM 9 Genetic Drift (Chapter 13) DEFINITION 9 change in frequencies in small populations due to chance earthquakes, floods, fires, large scale catastrophes may create genetic bottlenecks and rapidly shift gene frequencies TERM 10 3 Types of Natural Selection (Chapter 13) DEFINITION 10 1.) Stabilizing selection intermediate phenotype favored- selection against the extremes, loose extremes 2.)Directional selection one extreme phenotype favored-something in habitat changes 3.)Disruptive selection - both extreme phenotypes favored TERM 21 Earth's beginning Chapter 15 DEFINITION 21 earth was formed 4.6 billion years ago. 3.9 billion years ago- life TERM 22 Miller DEFINITION 22 Millers experiments with methane, ammonia, hydrogen, water and electrical sparks confirm the formation of organic molecules the energy source on early earth could have been lightening or heat from volcanoes and thermal vents TERM 23 Ages of fossils and rocks are used to construct the geological record DEFINITION 23 Eons > eras > periods > epochs Three eons Archaean, Proterozoic, and Phanerozoic TERM 24 Continental Drift Chapter 15 DEFINITION 24 o Pangaea forms 250 million years ago, breaks up about 180 million years ago o First break creates Laurasia and Gondwana o Last break forms continents o Continental drift helps explain the current distributions of many plants and animals such as lung fish and marsupials o Continental drift can endanger humans TERM 25 Mass Extinction Chapter 15 DEFINITION 25 o Five mass extinctions o Causes Volcanic eruptions, large comets or asteroids hitting earth o Consequences many life forms lost it may take 5 10 million years for new species to rebound, o Will man create the 6th mass extinction TERM 26 Evolution DEFINITION 26 Evolution is the change in the inherited traits of a population of organisms through successive generations. Evolution is not directed no end point is targeted o Species selection some new species arise = birth others go extinct = die. This model is macroevolution is called species selection TERM 27 Phylogenetic Tree DEFINITION 27 A phylogenetic tree or evolutionary tree is a branching diagram or "tree" showing the inferred evolutionary relationships among various biological species or other entities based upon similarities and differences in their physical and/or genetic characteristics. o Analogies result from convergent evolution species from different evolutionary branches = no shared ancestry similar appearance examples wings of bees and bats, Australian mole an North American mole both look similar, they occupy the same niche. TERM 28 Species Hierarchy DEFINITION 28 Domain > Kingdom > phylum > class > order > family > genus > species TERM 29 Parsimony DEFINITION 29 simplest explanation for an observed pattern = used to interpret data in developing phylogenetic trees TERM 30 Genomes DEFINITION 30 the genome is the entirety of an organism's hereditary information. we share 99% of our genes with chimps, 80% with insects, 50% with yeast TERM 31 Molecular clocks DEFINITION 31 a technique in molecular evolution that uses fossil constraints and rates of molecular change to deduce the time in geologic history when two species or other taxa diverged. some genes accumulate mutations at a steady rate, this allows us to create clocks to estimate the origins of new clades not found in fossil record TERM 32 Animal DEFINITION 32 Heterotrophic eukaryote that ingest food