Intro to Genetics

Intro to Genetics

Inheriting Traits

• Heredity - the passing of traits from parents to offspring

Key Terms

• Gene: Segment of DNA on chromosomes that codes for specific traits

• Allele: Different forms of a gene, need two for traits

• Trait: A characteristic being observed

Multiple Choice

How many alleles does an individual inherit for each gene?

• 1

• 2

• 3

• 4

Traits

Genotype: Genetic makeup of a trait

BB

Phenotype: Physical appearance of a trait

Blue Body

Multiple Choice

T/F

Genotype is the physical appearance of a trait

• True

• False

Traits

Homozygous: same copies of alleles in an organism

Ex. TT = purebred

Heterozygous: different copies of alleles

Ex. Tt = hybrid

Multiple Choice

Homozygous means....

• Having two identical alleles

• Having two different alleles

Alleles

Dominant: allele that dominants expression of gene

Noted by capital letters

Example: Tall = T

Recessive: Allele hidden/masked by other allele, only shows when homozygous

Noted by lower case letters

Example Short = t

Multiple Choice

Dominant is shown by...

• Lowercase letters

• Capital letters

Mendal's Experiment

Crossbred a purebred dominant plant with the opposite purebred recessive plant (PPxpp)

This resulted in a hybrid (F1) generation

Mendel's Experiment Continued

Crossbred the resulting hybrid (F1) generation plants

The offspring (F2) generation resulted in three dominant and 1 recessive plant

75% dominant and 25% recessive

PP, Pp, Pp, pp

Ending Video

https://www.britannica.com/video/189080/video-traits-Punnett-square-Gregor-Mendel-way