Bio Chapter 11

A couple has 5 children, all sons. If the woman gives birth to a sixth child, what is the probability that the sixth child will be a son?

1/2

Assume that genes A and B are not linked. If the probability of allele A in a gamete is ½ and the probability of allele B in a gamete is ½, then the probability that both A and B are in the same gamete is

1/2 x 1/2

In Mendel's pea plants, yellow seeds are dominant to green seeds. Purple flowers are dominant to white flowers. Use Y and y for the seed color alleles and and P and p for the flower color alleles. Flower color and seed color assort independently. If a YyPp plant is crossed to a Yypp plant, what is the probability that the resulting plant will have the genotype Yypp (Hint: determine two separate probabilities, and use the rule of multiplication

1/4

In a species that has five different alleles for a gene at a particular locus, how many different alleles may be present in the somatic cells of one diploid individual

2

If a zygote has the genotype XYY, how many total chromosomes were in the sperm before it fused with the egg

24

How many unique gametes could be produced through independent assortment by an individual with the genotype AABbCCDdEE

4

In Mendel's pea plants, yellow seeds are dominant to green seeds. If a true-breeding, green-seed producing plant is crossed to a heterozygous yellow-seed producing plant, what percentage of offspring produces green seeds?

50 percent

If Individual 6 marries a woman with the disease, what is the probability that their first child will have the disease?

50%

How many different genotypes are possible from the cross of AaBb and AaBb

9

Which of the following is the most likely mode of inheritance for the disease?

Autosomal Recessive

Which of the following can be diagnosed by examining a karyotype of an individual's white blood cells

Down Syndrome

A child is born with blood type A to a mother with blood type B. The father must have which of the following blood types?

Either AB or A

Coat color in mice is determined by genes at two loci. When black mice from a particular population mate, they produce offspring in the following ratios: 9 black: 3 brown: 4 white. These results suggest that white coat color is expressed as a result of

Epistasis

What is nondisjunction

Failure of homologous chromosomes or sister chromatids to separate in meiosis

A woman who is a carrier for the hemophilia gene has a child with a man who does not have hemophilia. Which prediction is correct

Half of the sons and none of the daughters will have hemophilia

What is the physical basis for the independent assortment observation that Mendel made?

Homologous chromosomes are randomly separated during meiosis I.

A, B and O blood type in humans is controlled by a single gene with three alleles: IA, IB, and i. Type O is the recessive trait. The i allele is recessive to both IA and IB. Which of the following could be possible genotypes of the parents of a person with type O blood

IAi and IBi

Crossing flowering snapdragons with white flowering snapdragons yields seeds that grow into snapdragons with pink flowers. This suggests that

Incomplete dominance is occurring

Thomas Hunt Morgan, working with fruit flies, discovered that male fruit flies could have the mutant trait of white eyes, even if they only had one "white" allele. What was the significance of this finding

It allowed him to assign the trait of eye color to the X chromosome

A woman who does not carry the color-blindness allele has children with a man who is color blind. What proportion of their children will be color blind?

None

If Individual 2 were to marry a woman with no family history of the diseases, which of the following would most likely be true of their children?

None of the children would have the diseases

Which of the following best describes the parents in a testcross?

One individual has the dominant phenotype and the other has the recessive phenotype

The F1 offspring of Mendel's classic pea cross always looked like one of the two parental varieties because

One phenotype was completely dominant over another

In peas the trait for tall plants is dominant (T) and the trait for short plants is recessive (t). The trait for yellow seed color is dominant (Y) and the trait for green seed color is recessive (y). A cross between two plants results in 296 tall yellow plants and 104 tall green plants. Which of the following are most likely to be the genotypes for the parents

TTyy x TTYy

In humans, red-green colorblindness is a sex-linked recessive trait. If a man and a woman produce a color-blind son, which of the following must be true

The mother carries the allele for color blindness

Cystic fibrosis (CF) is caused by a recessive allele. A child has CF, even though neither of his parents has CF. What can you conclude about the parents

They are both heterozygous for the CF gene

A plant that produces white flowers is crossed to a plant that produces orange flowers. All the offspring produce pale orange flowers. What can you conclude

This trait shows incomplete dominance

Which of the following is a transfer of genes between nonhomologous chromosomes

Translocation

An autosomal recessive disorder

Will appear only in children of parents who both carry the gene

A and a are dominant and recessive alleles, respectively, of the same gene. Which genotype(s) would result in an individual with the recessive phenotype

aa only

Which type of inheritance is most likely to display a bell curve of phenotypes?

polygenic inheritance

Black fur in mice (B) is dominant to brown fur (b). Short tails (T) are dominant to long tails (t). What fraction of the progeny cross BbTt x Bbtt will have black fur and long tails

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