WorksheetsModule 10
Total questions: 11
Worksheet time: 6mins
When Mendel crossed yellow-seeded and green-seeded pea plants, all the offspring were yellow-seeded. When he took these F1 yellow-seeded plants and crossed them to green-seeded plants, what approximate genotypic ratio was observed?
1:2:1
1:1
3:1
1:1:1:1
Given the following genotypes for two parents, AABBCc × AabbCc, assume that all traits exhibit simple dominance and independent assortment. What proportion of the offspring of this cross will be expected to phenotypically resemble the parent with the genotype AABBCc?
1
1/4
3/8
3/4
Mendel's law of independent assortment has its basis in which of the following events of meiosis I?
the division of cells at telophase
crossing over of homologous pairs of duplicated chromosomes
alignment of pairs of homologous duplicated chromosomes along the middle of the cell
synapsis of homologous duplicated chromatids
Phenylketonuria is an inherited disease caused by a recessive autosomal allele. If a woman and her husband are both carriers, what is the probability that their first child will be a phenotypically normal girl?
3/4
3/8
3/16
1/4
Which of the following inheritance patterns describes the ability of a single allele to have multiple phenotypic effects?
epistasis
multiple alleles
incomplete dominance
pleiotropy
Which of the following calculations requires the use of the addition rule of probability?
Calculate the probability of a child having sickle-cell anemia OR cystic fibrosis (both autosomal recessive disorders) if parents are each heterozygous for both.
Calculate the probability of a child having both cystic fibrosis AND polydactyly (an autosomal dominant condition) when parents are each heterozygous for both genes.
Calculate the probability of a child having cystic fibrosis (an autosomal recessive disorder) if the parents are both heterozygous.
Calculate the probability that after a couple has had two children, the third child will be a girl.
The following question refers to the pedigree chart in the figure for a family, some of whose members exhibit the dominant trait, W. Affected individuals are indicated by a dark square or circle.What is the likelihood that the offspring of IV-3 and IV-4 will have the trait?
75%
50%
0%
100%
In mice and many other mammals, one gene controls production of fur color pigment (black or brown), and another gene determines whether the pigment is deposited in the fur. A mouse could have the genotype for coloration that produces black pigment, but if it has a genotype for the pigment deposition gene that prevents that pigment from being deposited in the fur, the mouse is white. This is an example of:
pleiotropy
epistasis
codominance
incomplete dominance
Hutchinson-Gilford progeria is an exceedingly rare human genetic disorder in which there is very early senility and death, usually from coronary artery disease, at an average age of 13 years. Patients, who look very old even as children, do not live to reproduce. Which of the following statements represents the most likely assumption regarding this disorder?
The disorder will increase in frequency in successive generations within a family.
The disease is autosomal dominant.
Each patient will have had at least one affected grandparent or parent.
The disorder may be due to a mutation in the DNA of a gamete from one of the parents.
Skin color in a certain species of fish is inherited by a single gene with four different alleles. How many different types of gametes would be possible in this organism?
16
8
4
2
Image that you breed together heterozygous purple-flowered, long-pollened pea plants and get mostly purple-flowered, short-pollened plants and white-flowered, long-pollened plants, with a very few purple-flowered, long-pollened or white-flowered, short-pollened plants. What is the most likely explanation?
Long pollen is often lethal, so few plants with long pollen survive to adulthood.
The genes are linked.
The purple allele influences pollen to become shorter.
One of the genes in question resides on a sex chromosome.
This is a normal random variation from the expected ratio for independent assortment.
