Genetics

Why you look like you do

What is the study of GENETICS? Who discovered Genetics and how did he do this?

*The study of Genetics is Heredity. *Gregor Mendel discovered Genetics through studying Pea Plants. *He used them to observe his prediction of how traits would be transferred from one generation to the next.

Terms you should know

*Dominant allele: the observed trait that masks the recessive trait. ~ T  *Recessive allele: trait that can be masked by the dominant trait. ~ t  *Heterozygous: two different allels for a trait. ~ Tt  *Homozygous: two identical alleles for a trait. ~ tt, TT  *Genotype: combinations of genes in an organism. ~ TT, Tt, tt  *Phenotype: outward apperance of an organism. reguardless of its genes. ~Purple, Pink

A simple cross in a punnett square

*Genotype: BB - 25%, Bb - 50%, bb - 25%  *Phenotype: Purple - 75%, White - 25%  *B = purple, b = white

Sex linked traits

These traits are controlled by genes located on the sex chromosomes.    *Examples~ Color blindness; mom is the carrier, males have only one X chromosome so if the trait ison the X chromosome they will be colorblind