bio 181 exam 1 (kosal) with 100% correct answers

bio 181 exam 1 (kosal)Compare and contrast the different mechanisms of speciation (allopatric, sympatric, parapatric, peripatric). - correct answer -Allopatric speciation takes place when populations are geographically isolated. Volcano explodes and populations are divided. -Sympatric occurs without geographic isolation. Occurs through the process of polyploidy: producing individuals with more than two sets of chromosomes. It is a genetic change within a population. -Parapatric speciation is when a new habitat is entered that is adjacent to the original habitat. Door is open. -Peripatric speciation is when an adjacent habitat is entered but it is isolated from the original habitat. Door is closed. Founder effect - correct answer change in allele frequencies as a result of the migration of a small subgroup of a population. New group is different from old population. Bald guys start a new island, tons of bald guys on the island. Gradualism - correct answer The theory that evolution occurs slowly but steadily Define reproductive isolation (pre-zygotic and post-zygotic) and apply these definitions to specific examples. - correct answer Pre-zygotic: before the egg meets the sperm. -Ecological isolation -Behavioral isolation -Temporal isolation -Mechanical isolation -Prevention of gamete fusion Post-zygotic: after the egg meets the sperm