Bio 109 Final Ch. 19

What is the likelihood that a parent with type AB blood would have a child with type O blood?

0%

Nondisjunction in meiosis I results in failure of __________.

homologous chromosomes to separate

Based on the information below, answer the following three questions, assuming complete dominance. "In humans, the ability to roll the tongue is a dominant trait; the inability to roll the tongue is a recessive trait." If two individuals homozygous dominant for this trait have a child, what is the chance that the child will not be able to roll his tongue?

0%

How many different kinds of gametes (with respect to a particular gene locus) are formed by an individual who is homozygous at that locus?

1

Based on the information below, answer the following three questions, assuming complete dominance. "In humans, the ability to roll the tongue is a dominant trait; the inability to roll the tongue is a recessive trait." If an individual homozygous dominant for this trait has a child with an individual who cannot roll his tongue, what is the chance that the child will have a heterozygous genotype?

100%

Based on the information below, answer the following two questions, assuming complete dominance. "In humans, a widow's peak is a dominant trait, and a straight hairline is a recessive trait." If an individual homozygous dominant for widow's peak has a child with an individual heterozygous for widow's peak, what is the chance that the child will have a widow's peak?

100%

Two parents are heterozygous for familial hypercholesterolemia, with blood cholesterol levels two to three times the normal level. What is the probability that their child will be unaffected by this disorder?

25%

Based on the information below, answer the following two questions, assuming complete dominance. "In humans, a widow's peak is a dominant trait, and a straight hairline is a recessive trait." If an individual homozygous dominant for widow's peak has a child with an individual heterozygous for widow's peak, what is the chance that the child will have a homozygous dominant genotype?

50%

Which of the following statements correctly expresses the relationship between dominant and recessive alleles?

A dominant allele masks the expression of a recessive allele in a heterozygote.

Which of the following could be detected by preparing a karyotype?

Klinefelter syndrome

Examination of a karyotype reveals 23 pairs of chromosomes, with each homologous pair illustrating similar size and centromere location. Which of the following can be concluded from this karyotype?

The individual is a female.

A man carries a Y-linked trait. He will pass this trait on to __________.

all of his sons

In humans, the allele for a widow's peak (W) is dominant and the allele for a straight hairline (w) is recessive. This trait shows complete dominance. Which of the following represents the possible phenotypes in the offspring of two parents, both with a straight hairline?

all offspring will have a straight hairline

A recessive phenotype will be expressed when __________.

both alleles present are recessive

In the human ABO blood-typing system, an individual with A and B alleles will express both A and B phenotypes on his or her red blood cells. This is an example of __________.

codominance

Dominant alleles that cause disease are especially dangerous because __________.

heterozygous individuals will develop the disease

If both alleles of a particular gene are identical, the person is said to be

homozygous

An example of a genotype is

homozygous dominant

When a straight-haired parent and a curly-haired parent have a wavy-haired child, this is an example of __________.

incomplete dominance

Alterations in chromosomal structure or number that occur during mitosis or meiosis are seldom seen because __________.

the altered genes are crucial to development and the organism does not survive to birth

When a piece of chromosome breaks off and reattaches at another site on the same or another chromosome, this is called

translocation

A deletion occurs when a piece of chromosome breaks off and is lost. T/F

true