genetic inheritance

human bio

meiosis

type of cell division that eventually produces 4 genetically different cells

random chromosome assortment

chromosomes separate independently

random fertiliization

the sperm and the oocyte join independetly

crossing over

homologous chromosomes pair up and exchange pieces

genotype

a persons full genetic makeup

phenotype

persons visual characteristics

allele types

variation of a gene

dominant

expresses itself is present

recessive

only expresses itself in the homozygous state

homozygous

two of the same alleles

heterozygous

two different ales, one dominant and one recessive

dominant and recessive

the simplest genetic system

punnet square

tool used to estimate the genotype and phenotype percentages of the offspring

codominance

both alleles are expressed

ABO blood groups

dominant if present

multiple alleles

more than two alleles in a population

incomplete dominance

heterozygous has a phenotype that is in between the two homozygous

example: wavy hair

polygenetic

range in the phenotype which shows its controlled by two or more genes, thus four or more alleles

examples: skin color and height

sex-linked-inheritance

found on sex chromosomes usually the X

examples: color blindness and hemophilia

pedigree charts and disorders

a diagram that shows the distribution of a disorder through family generation

autosomal

non-sex chromosome or characteristic

autosomal recessive

only shows up if you are homozygous recessive

carrier

has an allele for the disorder, but does not show or have the disorder

autosomal dominant

expresses itself through genetics