Punnett Squares Flashcard

Front

What is a Punnett Square?

Back

A Punnett Square is a diagram used to predict the genotype and phenotype combinations of a genetic cross.

Front

What does homozygous mean?

Back

Homozygous refers to having two identical alleles for a particular gene, either dominant or recessive.

Front

What does heterozygous mean?

Back

Heterozygous refers to having two different alleles for a particular gene, one dominant and one recessive.

Front

What is the phenotype?

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 genotype?

Back

The genotype is the genetic constitution of an individual, specifically the alleles present for a particular gene.

Front

What is the probability of obtaining a homozygous recessive offspring from a cross between two heterozygous parents?

Back

25%.

Front

What is the expected phenotype ratio from a monohybrid cross?

Back

The expected phenotype ratio is typically 3:1 for dominant to recessive traits.

Front

What is the expected genotype ratio from a monohybrid cross between two heterozygous parents?

Back

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

Front

What is the significance of dominant and recessive alleles?

Back

Dominant alleles mask the effect of recessive alleles in heterozygous individuals, determining the phenotype.

Front

How do you determine the genotype of an organism with a dominant phenotype?

Back

You can determine the genotype by performing a test cross with a homozygous recessive individual.