Genetics & Punnett Square

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., BB, Bb, bb).

Front

What is a heterozygous genotype?

Back

A heterozygous genotype has two different alleles for a trait, such as Bb.

Front

What is a homozygous genotype?

Back

A homozygous genotype has two identical alleles for a trait, such as TT (homozygous dominant) or tt (homozygous recessive).

Front

What does it mean for an allele to be dominant?

Back

A dominant allele is one that expresses its trait even when only one copy is present (e.g., T in Tt).

Front

What does it mean for an allele to be recessive?

Back

A recessive allele only expresses its trait when two copies are present (e.g., tt).

Front

What is a phenotype?

Back

A phenotype is the observable physical or biochemical characteristics of an organism, determined by its genotype.

Front

What is a hybrid organism?

Back

A hybrid organism is the offspring resulting from the cross of two different traits or varieties, such as Tt from Tt x Tt.

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the genetic outcomes of a cross between two organisms.

Front

How do you calculate the probability of a trait in offspring?

Back

The probability is calculated by dividing the number of favorable outcomes by the total number of possible outcomes.

Front

In a Tt x Tt cross, what are the possible genotypes of the offspring?

Back

The possible genotypes are TT, Tt, Tt, and tt.