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 the term 'dominant allele' mean?

Back

A dominant allele is an allele that expresses its trait even when only one copy is present in the genotype.

Front

What does the term 'recessive allele' mean?

Back

A recessive allele is an allele that only expresses its trait when two copies are present in the genotype.

Front

What is the genotype of an organism with two identical alleles?

Back

Homozygous.

Front

What is the genotype of an organism with two different alleles?

Back

Heterozygous.

Front

In a heterozygous genotype, which allele is expressed in the phenotype?

Back

The dominant allele.

Front

What is the phenotype of an organism?

Back

The phenotype is the observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.

Front

What is the significance of the X and Y chromosomes in determining gender?

Back

The presence of one X and one Y chromosome typically determines a male, while two X chromosomes typically determine a female.

Front

What is the expected phenotypic ratio in a monohybrid cross of two heterozygous parents (Aa x Aa)?

Back

The expected phenotypic ratio is 3:1 (3 dominant: 1 recessive).

Front

What is the expected genotypic ratio in a monohybrid cross of two heterozygous parents (Aa x Aa)?

Back

The expected genotypic ratio is 1:2:1 (1 homozygous dominant: 2 heterozygous: 1 homozygous recessive).