Lesson 14 BIO

A woman is red-green colorblind. Her husband does not exhibit this sex-linked trait. Which statement describes their children?

A woman is red-green colorblind. Her husband does not exhibit this sex-linked trait. Which statement describes their children?

All boys will be color blind, none of the girls will be color blind

Aneuploidy arises when ____.

Chromosomes fail to segregate properly during meiosis

If a son inherits an X-linked mutant allele, the trait is expressed because ____.

Males have only one copy of the allele

Which of the following statements describes a correct relationship between a gene, a protein, and a chromosome?

A gene is a segment of a chromosome that encodes a protein.

Martha exhibits an autosomal dominant disorder. One of her parents does not possess the disorder, but the other parent does. What are Martha's chances of having a child with the disorder if she marries a man who does not have the disorder?

50%

The presence of a single mutant allele causes a female to develop Huntington's disease. This disease is most likely inherited as ____.

An autosomal dominant trait

A karyotype of a diploid organism shows three #9 chromosomes. This condition is described as ____.

Trisomy 9

A condition known as Cri du chat is exhibited by individuals in which a portion of the short arm of chromosome 5 is shorter than normal. This disorder arises when a gamete with a chromosomal abnormality fuses during fertilization, but what causes the chromosomal abnormality?

A deletion during crossing over in meiosis

One of the chromosomes in a karyotype has a portion of another chromosome added to it. This is an example of _____.

Translocation

A complete extra chromosome in an individual's genome is most likely caused by ____.

Nondisjunction

How many Barr bodies would you expect to find in a cell isolated from the body of a normal female?

1

In a pedigree chart, a fully shaded square represents ____.

An affected male

A daughter is diagnosed with PKU at birth. Neither parent exhibits the disease. What is the most likely pattern of inheritance?

Autosomal recessive

A human child whose genome includes an SRY segment is ____.

A male

A father has Duchenne muscular dystrophy, an X-linked recessive disorder. The mother is not a carrier. Which statement describes their children?

All the girls will be carriers, none of the boys will have Duchenne muscular dystrophy

A young man has adrenoleukodystrophy. In reviewing his family history, you notice uncles, grandfathers, and other males on his mother's side of the family who have the disease, but no females. His father's side of the family has no history of the disease. What is the most likely pattern of inheritance?

X-linked recessive

Anntina has an autosomal recessive disorder called xeroderma pigmentosum. Her husband has a family history of this disorder and is tested for the mutant allele. He discovers he is a carrier. What are their chances of having a child with the disorder?

50%

A co-worker has 6 fingers on each hand. He tells you that his mother and grandfather also have the extra digits on their hands. As far back as the family can remember, someone in each generation on his mother's side of the family has had 6 fingers on each hand. What is the most likely pattern of inheritance?

Autosomal dominant

Because the gene for hairy ears is located on the Y chromosome, _____.

Girls cannot have hairy ears

An image displaying paired chromosomes aligned according to their size is a _____.

Karyotype

In human females, dosage compensation is required to _____.

Reduce expression of X-linked genes to maintain proper development and cell function

A woman has a sex-linked recessive disorder. Her husband does not have the disorder. She discovers she is pregnant with a boy. What are the chances her son will be born with the disorder?

100%

A child is born with albinism. The father expresses the trait, but the mother does not. Neither parent has a family history of albinism. What is the most likely pattern of inheritance?

Autosomal recessive

A woman whose father had cystic fibrosis marries a man with cystic fibrosis (CF). The man's parents did not have cystic fibrosis. What is the likelihood that this couple's first child will have CF?

50%

The human genome contains _____.

22 pairs of autosomes and one pair of sex chromosomes