Punnett Square

Homozygous

"Purebread" having two identical alleles for a trait Ex) BB

Recessive

A trait that his hidden by a dominant trait. Need two traits for it to be expressed. (ex. bb)

Genotype

Letters expressing the types of genes.

The probability is 50%

One cat carries heterozygous, short-haired traits, and its mate carries homozygous long-haired traits. Use a Punnett square to determine the probability of one of their offspring having short hair.

The probability is 75%

One flower is hybrid red and it is crossed with a heterozygous red flower. Use a Punnett square to determine the probability of one of their offspring having a red color.

Allele

One gene from a pair Ex) T or t

physical appearance

Phenotype refers to the ______________________ of an individual.

The probability is 100%

Red flowers are dominant to white flowers. A homozygous red flower is crossed with a homozygous white flower. Use a Punnett square to determine the probability of one of their offspring having red color.

The probability is 0%

Red flowers are dominant to white flowers. A purebred red flower is crossed with a white flower. Use a Punnett square to determine the probability of one of their offspring having a white color.

What do Punnett Squares show?

They show the probability of offspring inheriting particular genetic combinations.

Heterozygous

Two different alleles for a trait. "scientific name" Ex) Bb

The probability is 25%

Two heterozygous red flowers are crossed. Use a Punnett square to determine the probability of one of their offspring having a white color.

dominant

When the genotype consists of a dominant and a recessive allele, the phenotype will be like _________________ allele.

Dominant

a trait that is always expressed. It prevents a recessive from being expressed.

Phenotype

physical appearance of the gene Ex. tall, brown eyes, etc

Punnett Square

used to determine all the possible genotypes and phenotypes that offspring can inherit from their parents

Hybrid

when the alleles are different (Bb) "common name"

Purebred

when the alleles are the same (BB or bb) "common name"