Punnett Square Review for 2nd 9 Week Exam

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.

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What does homozygous mean?

Back

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

Front

What does heterozygous mean?

Back

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

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What is a genotype?

Back

A genotype is the genetic makeup of an organism, represented by the alleles it possesses.

Front

What is a phenotype?

Back

A phenotype is the physical expression or characteristics of a trait in an organism, influenced by its 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 expressed only when two copies are present.

Front

What does it mean if an organism is purebred?

Back

A purebred organism has a homozygous genotype, meaning it has two identical alleles for a trait.

Front

What is the purpose of a test cross?

Back

A test cross is used to determine the genotype of an organism with a dominant phenotype by crossing it with a homozygous recessive organism.

Front

What is the expected genotype ratio from a monohybrid cross?

Back

The expected genotype ratio from a monohybrid cross is 1:2:1 (homozygous dominant : heterozygous : homozygous recessive).

Front

What is the expected phenotype ratio from a monohybrid cross?

Back

The expected phenotype ratio from a monohybrid cross is 3:1 (dominant : recessive).