Heredity and Genetics Test Review

Front

What is a gene?

Back

A piece of DNA on a chromosome that codes for a trait.

Front

Which individual in the first generation is a carrier?

Back

The male.

Front

What is the dominant trait in pea seeds?

Back

Yellow pea seeds.

Front

In a Punnett square, if white petal color (W) is dominant over purple petal color (w), how many offspring will have the white phenotype?

Back

3.

Front

Which of the following is true: 1, 2, and 3 are carriers; 1 and 2 are the grandparent generation; 3 and 4 have heterozygous genotypes; 2 has the dominant phenotype?

Back

3 and 4 have heterozygous genotypes.

Front

What is the definition of a dominant trait?

Back

A trait that is expressed in the phenotype even when only one copy of the allele is present.

Front

What is a recessive trait?

Back

A trait that is only expressed in the phenotype when two copies of the allele are present.

Front

What does homozygous mean?

Back

Having two identical alleles for a particular gene.

Front

What does heterozygous mean?

Back

Having two different alleles for a particular gene.

Front

What is a Punnett square used for?

Back

To predict the genotypes and phenotypes of offspring from a genetic cross.