Punnett squares

Front

What is a Punnett square?

Back

A Punnett square is a diagram used to predict the genetic makeup of offspring from two parents based on their alleles.

Front

What does homozygous mean?

Back

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

Front

What does heterozygous mean?

Back

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

Tags

NGSS.HS-LS3-2

Front

What is the probability of obtaining homozygous alleles from a Punnett square with two heterozygous parents?

Back

50%.

Tags

NGSS.HS-LS3-3

Front

What is incomplete dominance?

Back

Incomplete dominance is a genetic situation where one allele does not completely dominate another, resulting in a third phenotype that is a blend of the two.

Front

If a red flowered plant (RR) is crossed with a white flowered plant (WW) and the result is pink flowers (RW), what type of dominance is this?

Back

This is an example of incomplete dominance.

Front

In a Punnett square, what does each box represent?

Back

Each box represents a possible genotype of the offspring resulting from the combination of alleles from the parents.

Front

What is the expected phenotype ratio for a monohybrid cross between two heterozygous parents?

Back

The expected phenotype ratio is 3:1.

Tags

NGSS.HS-LS3-3

Front

What is the genotype of a plant that is homozygous recessive for height if T = tall and t = short?

Back

The genotype is tt.

Tags

NGSS.HS-LS3-1

Front

What is the significance of the letters used in a Punnett square?

Back

The letters represent different alleles of a gene, with uppercase letters typically indicating dominant alleles and lowercase letters indicating recessive alleles.