Chromosomal Mutations: Aneuploidy: Videos & Practice Problems

In a family, a man and a woman have a child with Klinefelter syndrome caused by nondisjunction during meiosis. The child has an extra X chromosome, resulting in a karyotype of 47, XXY.
What is the genotype of the abnormal chromosome?

Which of the following is the most likely genotype of the color-blind father in a family where a woman who is wild type (homozygous) and a man with color blindness have a daughter with Turner syndrome (XO) who has normal color vision and blood clotting?

What are the genotypes of the parents in a family where a man with color blindness and a woman with wild type (heterozygous) have a son with Jacob syndrome (XYY) who has hemophilia?

A man with color blindness and a woman with hemophilia have a daughter with Turner syndrome (XO) who is unaffected by both traits. What is the probability that the couple's next child will be a daughter with Turner syndrome once more?

Which breeding strategy will most likely produce a seedless variety of cucumber from two existing lines, line A is a tetraploid line, and line B is a diploid line?

What is the most likely explanation for the wide range of phenotypes observed in XX/XO and XY/XO mosaics?

The Down syndrome critical region (DSCR), which contains genes responsible for many features of Down syndrome, is located on which of the following chromosomes?.

How many chromosomes can a child with Down syndrome have?

Which of the following chromosomal arrangements reflects monosomy?

The gene "T" in pea plants controls their height. Which gene pair arrangement from the list below will reflect a trisomy?

In humans, autosomal monosomy of the chromosomes leads to early fetal death or miscarriage and is often not compatible with life. This is because:

Monosomics and trisomics are usually inviable in Drosophila, with the exception of those on chromosome 4. The eyeless gene (ey) is recessive to normal eye and is found on chromosome 4. Determine the genotype of the trisomics in F1 progeny when a diplo-4 eyeless female (ey ey) is crossed with a triplo-4 normal eyed male (ey⁺ ey⁺ ey⁺).

Monosomics and trisomics are usually inviable in Drosophila, with the exception of those on chromosome 4. The eyeless gene (ey) is recessive to normal eye and is found on chromosome 4. Determine the probabilty of haplo-4 eyeless (ey) F1 progeny when a diplo-4 normal eyed female (ey⁺ ey⁺) is crossed with a haplo-4 eyeless male (ey).

A karyotype analysis of amniotic fluid cells from a pregnant woman revealed the presence of two Barr bodies. Determine the chromosomal disorder that the fetus may have. 

Which of the following factors influences the likelihood of Down syndrome?

Which of the following is inherited from all ancestors?

Robertsonian translocation is a condition in which a chromosome becomes attached to another. What type of autosomal chromosome is typically affected by Robertsonian translocation?

Mosaic Turner syndrome happens when some of the individual's body cells have a pair of X chromosomes while the other body cells have only one. Hence, mosaicism may be caused by an error during _______.

Because it is encoded by the _____ gene, glucose-6-phosphate dehydrogenase deficiency is more common in men than in women.

One of the two X chromosomes in each cell of a female human is naturally inactivated during embryonic development. This process is known as:

How many Barr bodies does a person with the karyotype XYY have?

The inactive X chromosome present in mammalian female somatic cells is known as:

Of the following aneuploids, which one will give rise to a metafemale Drosophila?

Humans have 23 chromosome pairs and are diploid. However, an individual has an extra copy of chromosome 13 in addition to the homologous pair. Identify the name of this condition.

Why does Mosaic Turner syndrome tend to be less severe than monosomy X Turner syndrome?

Identify a condition that will result in fertile female Drosophila flies.

Klinefelter syndrome can affect the growth of testicles which can adversely impact testosterone production. Hence, which of the following tests can be used to diagnose this condition?

What are the causes of a variety of aneuploid conditions in humans?

Down syndrome results from the trisomy of which chromosome?

The phenomenon in which the genetic material is improperly separated causing one egg to contain two X chromosomes and leaving the other lacking an X chromosome is called: