BIOL 1202 Chapter : Learning Objectives Chp 24
Document Summary
Prevent fertilization: postzygotic isolation mechanisms- often prevents the hybrid zygote from developing into a viable, fertile adult. Concept 24. 2: speciation can take place with or without geographic separation: speciation can occurs in two ways: allopatric and sympatric, distinguish between allopatric and sympatric speciation, allopatric speciation other country . Occurs when gen flow is interrupted or reduced when a population is divided into geographically isolated subpopulations: sympatric speciation- takes place in geographically overlapping populations, define allopatric speciation. Describe the mechanisms that may lead to divergence of isolated gene pools. In allopatric speciation, once geographic separation has occurred, the separated gene pools may diverge. Different mutations arise, and natural selection and genetic drift may alter allele frequencies in different ways in the separated populations. Polyploidy: presence of extra sets of chromosomes in cells due to accidents during meiosis: has caused sympatric speciation in many plant species, autopolyploidy, allopolyploidy.
