Meiosis and Genetics Review

Front

What is a dominant gene?

Back

A dominant gene is a gene that masks the effect of a recessive gene. It is expressed in the phenotype even if only one copy is present.

Front

What is a recessive gene?

Back

A recessive gene is a gene that is masked by a dominant gene. It is only expressed in the phenotype when two copies are present.

Front

What does homozygous mean?

Back

Homozygous refers to an organism that has two identical alleles for a particular trait.

Front

What does heterozygous mean?

Back

Heterozygous refers to an organism that has two different alleles for a particular trait.

Front

What is the significance of capital letters in alleles?

Back

Capital letters represent dominant traits in alleles.

Front

What is a Punnett square?

Back

A Punnett square is a diagram used to predict the genetic outcomes of a cross between two organisms.

Front

If two heterozygous birds (Bb) mate, what is the probability of having a homozygous dominant offspring?

Back

The probability is 25%.

Front

What does it mean if an organism is hybrid?

Back

A hybrid organism has two different alleles for a particular trait, making it heterozygous.

Front

What is the phenotypic ratio of a monohybrid cross between two heterozygous parents?

Back

The phenotypic ratio is 3:1.

Front

What is the genotypic ratio of a monohybrid cross between two heterozygous parents?

Back

The genotypic ratio is 1:2:1.