Question 1

A carrier for a genetic disorder will pass the allele to all of their offspring.

Accepted Answer

Carriers of a genetic disorder have one copy of a mutated gene and one normal gene, meaning there is only a 50% chance of passing the mutated gene to each offspring if the disorder is autosomal dominant, and no guarantee of passing it on if the disorder is autosomal recessive and the other parent is not a carrier.

Question 2

When a fragment breaks from a chromosome and rejoins it, in a flipped orientation, the result is called a/an:

Accepted Answer

When a fragment breaks from a chromosome and rejoins it, but in a flipped orientation, the result is called an inversion. This can cause disruption of gene expression and potential problems during meiosis. Deletion refers to a loss of genetic material, polyploidy refers to having multiple sets of chromosomes, aneuploidy refers to having an abnormal number of chromosomes, and translocation refers to the exchange of genetic material between non-homologous chromosomes.

Question 3

A chromosome that has been broken and has lost a section has had a/an:

Accepted Answer

Deletion refers to the loss of a section of a chromosome. Aneuploidy refers to the loss or gain of an entire chromosome. Inversion refers to the reversal of the direction of a section of a chromosome. Duplication refers to the duplication of a section of a chromosome. Translocation refers to the movement of a section of a chromosome to a non-homologous chromosome.

Question 4

A person must have two alleles for hemoglobin S in order to suffer from sickle-cell anemia.

Accepted Answer

Sickle-cell anemia is a recessive genetic condition, meaning that a person must inherit two copies of the hemoglobin S gene (one from each parent) in order to develop the disease. If a person inherits only one copy of the gene, they are said to have sickle-cell trait, which typically causes no symptoms but can still have some health implications.

Question 5

What is a possible cause of the chromosomal aberration called a "duplication"?

Accepted Answer

Unequal crossing over can occur during meiosis when homologous chromosomes misalign and crossing over occurs at different points, resulting in one chromosome having a duplication and the other having a deletion.

Question 6

Women do not express X-linked recessive characters.

Accepted Answer

Women can express X-linked recessive traits if they inherit two copies of the recessive allele, one from each parent. However, men only need to inherit one copy of the recessive allele to express X-linked recessive traits because they only have one X chromosome.

Question 7

Polyploidy is better tolerated in plants than in animals.

Accepted Answer

This is because plants have a greater ability to tolerate changes in chromosome number due to their ability to undergo self-fertilization or cross-fertilization with related species, leading to the formation of new hybrid species. Additionally, plants also have a greater ability to regenerate and repair damaged tissue, allowing them to better tolerate the effects of genetic abnormalities caused by polyploidy. In contrast, animals are generally more sensitive to changes in chromosome number, which can lead to developmental abnormalities, infertility, or even death.

Question 8

Cri-du-chat syndrome babies are mentally challenged and have an abnormal larynx that makes sounds like the cry of a cat. This disorder is due to a/an:

Accepted Answer

Cri-du-chat syndrome is caused by a deletion in chromosome 5.

Question 9

A karyotype you are viewing shows an extra piece of chromosome 1 attached to chromosome 22. What type of abnormality caused this?

Accepted Answer

A translocation is the movement of a portion of one chromosome to another non-homologous chromosome. In this case, a piece of chromosome 1 has moved and become attached to chromosome 22.

Question 10

Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
-This produces cri-du-chat syndrome.

Accepted Answer

The answer of Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E)...

Question 11

Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
-This event may occur during meiosis I or meiosis II.

Accepted Answer

The answer of Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E)...

Question 12

A karyotype reveals that a woman is carrying a fetus that has 47 chromosomes. The test reveals that the genotype of the fetus is XXY. Which of the following statements is correct?

Accepted Answer

A fetus with 47 chromosomes and a genotype of XXY indicates that the fetus has an extra X chromosome, which is a characteristic of Klinefelter syndrome. Down syndrome is characterized by an extra copy of chromosome 21, which is not the case here. Turner syndrome is characterized by a missing X chromosome, which is also not the case here. An autosomal disorder would affect non-sex chromosomes, but the karyotype reveals a sex chromosome abnormality.

Question 13

Which of the following combinations of chromosomes would be found in a person afflicted with Turner syndrome?

Accepted Answer

Turner syndrome is caused by a missing or partially missing X chromosome, resulting in a monosomy (only one copy) of the X chromosome. This is represented as XO, where O denotes the missing chromosome.

Question 14

A single nondisjunction event results in some gametes with more chromosomes and some gametes with fewer chromosomes.

Accepted Answer

Nondisjunction occurs when chromosomes fail to separate during meiosis, resulting in gametes with an abnormal number of chromosomes. Some gametes may have an extra chromosome while others have a missing chromosome.

Question 15

What single attribute determines that a human fetus is male?

Accepted Answer

The presence of a Y chromosome is the determining factor for the development of male genitalia in a human fetus. The absence of a Y chromosome results in the development of female genitalia. Therefore, the correct option is C - the presence of a Y chromosome.

Question 16

Which of the following is a transfer of genes between non-homologous chromosomes?

Accepted Answer

Translocation involves the transfer of genes between non-homologous chromosomes. Duplication, crossing over, inversion, and deletion all involve gene transfer within or between homologous chromosomes.

Question 17

If one of your parents has Huntington disease and is heterozygous for the disorder, you have a 50 percent chance of inheriting the disease.

Accepted Answer

Since Huntington disease is an autosomal dominant disorder, if one parent has the disease and is heterozygous, the offspring has a 50 percent chance of inheriting the dominant allele for the disease.

Question 18

Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
-Only 1 percent of human embryos with this condition survive.

Accepted Answer

The answer of Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E)...

Question 19

Nondisjunction in somatic cells can result in aneuploid cells. This may give rise to:

Accepted Answer

Nondisjunction in somatic cells can lead to aneuploidy, which is a common feature of many cancers. This occurs when cells have abnormal numbers of chromosomes, which can cause irregular cell growth and division leading to the development of tumors.

Question 20

Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E) deletion
-Non-homologous chromosomes have exchanged parts.

Accepted Answer

The answer of Match the following.
A) aneuploidy
B) nondisjunction
C) duplication
D) translocation
E)...

Quiz 12: Units of Heredity: Chromosomes and Inheritance

A carrier for a genetic disorder will pass the allele to all of their offspring.

When a fragment breaks from a chromosome and rejoins it, in a flipped orientation, the result is called a/an:

A chromosome that has been broken and has lost a section has had a/an:

A person must have two alleles for hemoglobin S in order to suffer from sickle-cell anemia.

What is a possible cause of the chromosomal aberration called a "duplication"?

Women do not express X-linked recessive characters.

Polyploidy is better tolerated in plants than in animals.

Cri-du-chat syndrome babies are mentally challenged and have an abnormal larynx that makes sounds like the cry of a cat. This disorder is due to a/an:

A karyotype you are viewing shows an extra piece of chromosome 1 attached to chromosome 22. What type of abnormality caused this?

Match the following. A) aneuploidy B) nondisjunction C) duplication D) translocation E) deletion -This produces cri-du-chat syndrome.

Match the following. A) aneuploidy B) nondisjunction C) duplication D) translocation E) deletion -This event may occur during meiosis I or meiosis II.

A karyotype reveals that a woman is carrying a fetus that has 47 chromosomes. The test reveals that the genotype of the fetus is XXY. Which of the following statements is correct?

Which of the following combinations of chromosomes would be found in a person afflicted with Turner syndrome?

A single nondisjunction event results in some gametes with more chromosomes and some gametes with fewer chromosomes.

What single attribute determines that a human fetus is male?

Which of the following is a transfer of genes between non-homologous chromosomes?

If one of your parents has Huntington disease and is heterozygous for the disorder, you have a 50 percent chance of inheriting the disease.

Match the following. A) aneuploidy B) nondisjunction C) duplication D) translocation E) deletion -Only 1 percent of human embryos with this condition survive.

Nondisjunction in somatic cells can result in aneuploid cells. This may give rise to:

Match the following. A) aneuploidy B) nondisjunction C) duplication D) translocation E) deletion -Non-homologous chromosomes have exchanged parts.