Genotypes and Punnett Square Review

Front

What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses (e.g., PP, Pp, pp).

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene (e.g., PP or pp).

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene (e.g., Pp).

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 is the probability of an offspring being purple if both parents are homozygous dominant (PP)?

Back

100%.

Front

What is the probability of an offspring being purple if one parent is homozygous dominant (PP) and the other is homozygous recessive (pp)?

Back

100%.

Front

What is the probability of an offspring being purple if one parent is heterozygous (Pp) and the other is homozygous recessive (pp)?

Back

50%.

Front

What is the probability of an offspring being purple if both parents are heterozygous (Pp)?

Back

75%.

Front

What is the phenotype of an organism?

Back

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

Front

What is the difference between dominant and recessive alleles?

Back

A dominant allele is expressed in the phenotype even if only one copy is present, while a recessive allele is only expressed if two copies are present.