Chapter 26 Quiz 2

The chance of having a boy or a girl with each birth is 50%.

• True

• False

X-linked recessive disorders are more common in females.

• True

• False

Most human characteristics are controlled by a single gene.

• Ture

• False

Identical twins share all their traits because they have the same genetic makeup.

• True

• False

The pedigree shows the inheritance of a certain trait in a family. The trait is controlled by a pair of alleles located on an autosome.

Which cross(es) can be used to deduce which phenotype is dominant?

• Cross X only

• Cross Z only

• Crosses X and Y only

• Crosses X and Z only

The pedigree shows the inheritance of a certain trait in a family. The trait is controlled by a pair of alleles located on an autosome.

What are the probable genotypes of individual 1?

• Homozygous

• Heterozygous

• Homozygous or heterozygous

The pedigree shows the inheritance of a certain trait in a family. The trait is controlled by a pair of alleles located on an autosome.

What are the probable genotypes of individual 2?

• Homozygous

• Heterozygous

• Homozygous or heterozygous

Discontinuous variation has (a)______________ phenotypes. The data can be represented in a (b)______________.

• (a) intermediate, (b) line curve

• (a) intermediate, (b) bar chart

• (a) no intermediate, (b) line curve

• (a) no intermediate, (b) bar chart

Continuous variation has (c)______________ phenotypes. The data can be represented in a (d)______________.

• (c) intermediate, (d) line curve

• (c) intermediate, (d) bar chart

• (c) no intermediate, (d) line curve

• (c) no intermediate, (d) bar chart

Characteristics showing discontinuous variation are usually controlled by (e)______________ genes, while those showing continuous variation are usually controlled by (f)______________ genes.

• (e) one or a few, (f) many

• (e) many, (f) one or a few