Unit 1 Scientific Approaches Chapter 4 Genes and heredity

Basic Genetics 1.Genes are in pairs (alleles), one from each parent 2.dominant or recessive, homozygous or hetero 3.Genes segregate (separate) during reproduction 4.Genes assort independently, combos are random

Genotype- genetic makeup, genes Phenotype- what it physically looks like Polygenetic traits- come from combo of many genes Ex: nose shape, hair color

DNA Genes located on chromosomes Some are sex linked (carried on X) Central Dogma DNA --> RNA --> Protein

Haploid + Haploid= Diploid N + N = 2N 23 from mom + 23 from dad = 46 baby

What Genes Do Control body processes Are not expressed all the time Heritability: Behavior= Genetics + Environment

Genetic Mutation and Evolution 1. Mutations- random change in genes, lead to new phys or beh traits 2. Gene flow- mov’t of indiv in or out of pop which changes allele frequency 3. Genetic drift- changes in gene pool by chance (environment changes, disease, etc) 4. Nonrandom mating- sex selection

Genes and Behavior Different genes lead to Different proteins and amino acids which lead to Different behavioral traits

Selection Artificial selection- selective breeding for certain traits Making hybrids to combine breed traits Instinctive drift- behavior gravitates toward strong instinctive pattern even when learning or training contradicts it