Punnett Squares

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles from the parents.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene, such as TT or tt.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene, such as Tt.

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., TT, Tt, tt).

Front

What is a phenotype?

Back

A phenotype is the physical appearance or observable traits of an organism, resulting from the genotype.

Front

What is the difference between dominant and recessive alleles?

Back

Dominant alleles are expressed in the phenotype even if only one copy is present, while recessive alleles are only expressed if two copies are present.

Front

What is the expected genotype ratio from a monohybrid cross of two heterozygous parents (Tt x Tt)?

Back

The expected genotype ratio is 1 TT : 2 Tt : 1 tt.

Front

What is the expected phenotype ratio from a monohybrid cross of two heterozygous parents (Tt x Tt)?

Back

The expected phenotype ratio is 3 dominant : 1 recessive.

Front

If a homozygous dominant (TT) is crossed with a heterozygous (Tt), what are the possible genotypes of the offspring?

Back

The possible genotypes are 50% TT and 50% Tt.

Front

What does it mean if an organism is homozygous recessive?

Back

An organism is homozygous recessive if it has two recessive alleles for a trait, such as tt.