Evolution & Genetics: Micro & Macroevolution, Genes, Alleles, Genotypes, Phenotypes - Prof, Study notes of Biology

Download Evolution & Genetics: Micro & Macroevolution, Genes, Alleles, Genotypes, Phenotypes - Prof and more Study notes Biology in PDF only on Docsity! Handout for CHAPTER 15 – How Organisms Evolve Two related processes that occur in evolution Microevolution- small changes in a pop across generations. Macroevolution- accumulation of small changes- leads to new forms (species) Role of genes in evolution (basic definitions) Population- set of individuals of the same species in one area. Individuals- contains a unique set of genes Genes- section of DNA (found on chromosomes) that carry instructions for making proteins. Proteins- responsible for most structures and functions in an organism. (do all the work in the body, do everything) Difference between haploid and diploid organisms (# of copies of each gene) Prokaryotes have one copy of every gene (Haploid) Most Eukaryotes have 2 copies of every gene (Diploid) (one mom, one dad) Note: if Eukaryote uses sexual reproduction, they also have haploid cells- gametes (eggs, sperm) What are alleles? If you compare DNA of individualsin a population At a given gene, the instructions on the DNA may be the same or different Different instructions yield different proteins (forms) called ALLELES gene may have from 1 to 100s of alleles 5 The difference between genotype and phenotype Genotype- the alleles that an individual has in its DNA (its genetic makeup) Phenotype- how those alleles are expressed (seen) in the individual (Height, blood type, fur color, allergies, etx) An example from the book: hamster fur color (coat color) 2 alleles in this case B allele- black fur b allele- Brown fur 2 Homozygous genotypes 1 heterozygous genotype BB-black fur Bb-black fur bb-brown fur Black dominant to brown Phenotype- What you see is you get! Dominant trait. What are gene pools? Total gene pool – Sum of all the genes present in a popultaion. Gene pool for a single gene- sum of all the alleles for a gene in a popultaion. Each individual contributes to these gene pools. 5