Friday, January 12, 2024 - Intro to Traits

trait	allele	letter
height	tall short	T - dominant t - recessive
hair color	brown blonde	B - dominant b - recessive
eye color	brown blue	B - dominant b - recessive
hair type	curly straight	H - dominant h - recessive

trait

allele

letter

height

tall

short

T - dominant

t - recessive

hair color

brown

blonde

B - dominant

b - recessive

eye color

brown

blue

B - dominant

b - recessive

hair type

curly

straight

H - dominant

h - recessive

Gregor Mendel:

father of genetics
scientist in the 1800s
studied traits in the garden pea plant while living at a monestary
used 28,000 pea plants to record his data
data was able to support 3 laws of genetics
mendel’s laws

Mendel’s Laws:

Mendel’s Law of Dominance
dominants traits are expressed if it is present
Mendel’s Law of Segregation
allels are seperated during meiosis
each gamete recieves one allele of a trait
Mendel’s Law of Independent Assortment
the traits are seperated independently of all other traits in the organism

Heterozygous vs Homozygous

heterozygous genes are genes that:
have 2 different allels for one gene
also called “hybrid”
example; Aa
homozygous genes are genes that
have 2 of the same allele for one gene
also called “pure bred”
example; AA or aa

Genotype:

the genetic makeup of an individual
represented by letters for each allele

Phenotype:

the observable characteristics of an individual organism
what the offspring looks like

Punnet Square

possible outcomes of traits for offspring