Question 1

Answer the following questions in reference to the five items listed below.
-Following a gene duplication event involving only five loci,how many chromosomes will a human female have?
A)12
B)23
C)24
D)46
E)47

Accepted Answer

A gene duplication event does not change the number of chromosomes; it only increases the number of copies of certain genes. A human female will still have 46 chromosomes.

Question 2

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-Homologous sets of genes ABCDEF and aBCdEF are located on nonhomologous chromosomes.Crossing over between them is suppressed because their locations are the result of this.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

The situation described is characteristic of a translocation, which involves the exchange of segments between non-homologous chromosomes. In this case, there is a translocation of a homologous set of genes between non-homologous chromosomes, and crossing over between them is suppressed.

Question 3

Match the cause with the disorder.
-Down syndrome
A)autosomal recessive inheritance resulting in abnormally low melanin levels
B)nondisjunction of the twenty-first chromosomal pair
C)X-linked recessive inheritance
D)nondisjunction of the sex chromosomes

Accepted Answer

Down syndrome is caused by the nondisjunction of the twenty-first chromosomal pair, which results in an extra copy of chromosome 21.

Answer: A 
 Autosomal recessive inheritance resulting in abnormally low melanin levels is a cause of albinism.

Answer: D 
 Nondisjunction of the sex chromosomes can result in disorders such as Turner syndrome (only one X chromosome in females) or Klinefelter syndrome (an extra X chromosome in males).

Answer: C 
 X-linked recessive inheritance is a cause of disorders such as hemophilia and color blindness.

Question 4

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-The nucleotide sequences of homologous regions of DNA of two species are AATGCCCCGTTA and AATGCCCCGCTTA.If this is not the result of a nucleotide base-pair addition,then it is most likely the result of this.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

The difference between the two sequences is only one nucleotide, which suggests that a single base has been deleted from one of the sequences.

Question 5

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-Homologous sets of genes ABCDEF and AEDCBF are located on homologous chromosomes.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

The sequence of genes ABCDEF changing to AEDCBF on homologous chromosomes suggests an inversion, where a segment of the chromosome has been flipped to the opposite orientation.

Question 6

Select the disorder that best matches each the following statements.
-This disorder is an autosomal dominant disorder characterized by premature aging of body tissues.
A)Tay-Sachs disease
B)Turner syndrome
C)Progeria
D)Hemophilia A
E)Down syndrome

Accepted Answer

The statement describes Progeria, which is a rare genetic disorder that causes rapid aging in children. It is caused by a mutation in the LMNA gene and is inherited in an autosomal dominant pattern.

Question 7

Match the cause with the disorder.
-albinism
A)autosomal recessive inheritance resulting in abnormally low melanin levels
B)nondisjunction of the twenty-first chromosomal pair
C)X-linked recessive inheritance
D)nondisjunction of the sex chromosomes

Accepted Answer

Albinism is caused by an autosomal recessive inheritance resulting in abnormally low melanin levels.

Answer: C
 Nondisjunction of the sex chromosomes can cause disorders such as Turner syndrome and Klinefelter syndrome, but it is not associated with albinism.

Answer: B
 Nondisjunction of the twenty-first chromosomal pair is associated with Down syndrome, not albinism.

Question 8

Answer the following questions in reference to the five items listed below.
-How many chromosomes are present in each cell of the germ cell line for a tetraploid species whose diploid complement of chromosomes is 48?
A)12
B)23
C)24
D)46
E)47

Accepted Answer

A tetraploid species has four sets of chromosomes. Therefore, the germ cell line would have 4 sets of 24 chromosomes, which equals 96 chromosomes. However, the question asks how many chromosomes are present in each cell of the germ cell line, not the total number of chromosomes. Each germ cell contains half the number of chromosomes as a somatic cell. Therefore, each cell of the germ cell line would contain 24 chromosomes.

Question 9

Match the cause with the disorder.
-hemophilia A
A)autosomal recessive inheritance resulting in abnormally low melanin levels
B)nondisjunction of the twenty-first chromosomal pair
C)X-linked recessive inheritance
D)nondisjunction of the sex chromosomes

Accepted Answer

Hemophilia A is caused by X-linked recessive inheritance, meaning the gene mutation causing the disorder is on the X chromosome. This means males are more commonly affected, as they only have one X chromosome.

Answer: A 
 The disorder caused by autosomal recessive inheritance resulting in abnormally low melanin levels is albinism.

Answer: B 
 Nondisjunction of the twenty-first chromosomal pair results in Down syndrome, which is characterized by intellectual disability and distinct facial features.

Answer: D 
 Nondisjunction of the sex chromosomes can result in disorders such as Turner syndrome (XO) or Klinefelter syndrome (XXY). These disorders can cause a range of physical and developmental symptoms.

Question 10

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-A small region of a protein from three species is sequenced and found to be as follows:
species X is alanine,glycine,glycine,threonine,alanine
species Y is alanine,glycine,threonine,alanine
species Z is alanine,glycine,glycine,threonine,alanine
The difference in the amino acid sequence of species Y is most likely due to this.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

The difference in the amino acid sequence of species Y is a missing glycine, which suggests a deletion has occurred in the sequence of species Y compared to species X and Z.

Question 11

Choose the most appropriate answer for each.
-trisomy
A)3n; generally sterile
B)a chromosome segment is permanently transferred to a nonhomologous chromosome
C)(2n - 1); a zygote deprived of a chromosome
D)a repeat of a particular DNA sequence in the same chromosome or in nonhomologous ones
E)(2n + 1); three chromosomes of the same kind are present in a set of chromosomes
F)a piece of the chromosome is inadvertently left out during the repair process
G)a chromosome segment that has been cut out and rejoined at the same place, but backward

Accepted Answer

Trisomy is a condition where an individual has three chromosomes of the same kind instead of the usual two. It is indicated by the formula (2n + 1), where n is the number of chromosomes in a normal cell set.

Answer: C
 Trisomy is a condition where an individual has one extra chromosome, and the formula is (2n + 1). In the case of monosomy, one chromosome is missing, and the formula is (2n - 1).

Answer: A
 Trisomy is a condition where an individual has three chromosomes of the same kind instead of the usual two. It is generally sterile, meaning the individual is unable to reproduce.

Note: The other answer choices do not accurately describe trisomy.

Question 12

Answer the following questions in reference to the five items listed below.
-How many chromosomes does each somatic cell have in a human male who has two X chromosomes?
A)12
B)23
C)24
D)46
E)47

Accepted Answer

The answer of Answer the following questions in reference to...

Question 13

Choose the most appropriate answer for each.
-triploidy
A)3n; generally sterile
B)a chromosome segment is permanently transferred to a nonhomologous chromosome
C)(2n - 1); a zygote deprived of a chromosome
D)a repeat of a particular DNA sequence in the same chromosome or in nonhomologous ones
E)(2n + 1); three chromosomes of the same kind are present in a set of chromosomes
F)a piece of the chromosome is inadvertently left out during the repair process
G)a chromosome segment that has been cut out and rejoined at the same place, but backward

Accepted Answer

Triploidy refers to having three copies (rather than the normal two copies) of each chromosome in a cell. This results in a 3n (or sometimes 69, if referring to humans) chromosome number and is generally associated with infertility or developmental abnormalities.

Answer: C
 Monosomy refers to the loss of one (mono-) chromosome, resulting in a 2n-1 chromosome number (one less than the typical diploid number). This can be due to errors in cell division or chromosomal abnormalities.

Answer: E
 Trisomy refers to the presence of an extra (tri-) chromosome, resulting in a 2n+1 chromosome number. Down syndrome, for example, is caused by trisomy of chromosome 21.

Note: B, D, F, and G do not describe any of the given answer choices accurately.

Question 14

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-Homologous sets of genes ABCDEF and ABCDEF are located on nonhomologous chromosomes.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

Translocation is the process where a segment of a chromosome is moved to a nonhomologous chromosome, which matches the scenario of homologous sets of genes being located on nonhomologous chromosomes.

Question 15

Match the cause with the disorder.
-red-green color blindness
A)autosomal recessive inheritance resulting in abnormally low melanin levels
B)nondisjunction of the twenty-first chromosomal pair
C)X-linked recessive inheritance
D)nondisjunction of the sex chromosomes

Accepted Answer

Red-green color blindness is primarily caused by a genetic mutation on the X chromosome, resulting in X-linked recessive inheritance. This means that the disorder is more commonly seen in males, who have only one X chromosome, and can inherit the mutation from their carrier mother.

The other answer choices do not match the disorder:
A) Abnormally low melanin levels can cause albinism, not color blindness.
B) Nondisjunction of the twenty-first chromosomal pair results in Down syndrome, not color blindness.
D) Nondisjunction of the sex chromosomes can result in conditions like Klinefelter syndrome or Turner syndrome, but not color blindness.

Question 16

Match the cause with the disorder.
-Turner syndrome
A)autosomal recessive inheritance resulting in abnormally low melanin levels
B)nondisjunction of the twenty-first chromosomal pair
C)X-linked recessive inheritance
D)nondisjunction of the sex chromosomes

Accepted Answer

Turner syndrome is caused by nondisjunction of the sex chromosomes, leading to a female typically having only one X chromosome instead of two.

Question 17

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement.
-A small region of a protein from three species is sequenced and found to be as follows:
species X is alanine,glycine,threonine,alanine
species Y is alanine,glycine,threonine,alanine
species Z is alanine,valine,glycine,threonine,alanine
The difference in the amino acid sequence of species Z is most likely due to this.
A)Inversion
B)Deletion
C)Gene duplication
D)Translocation
E)Insertion

Accepted Answer

The difference in amino acid sequence between species Z and X/Y can be attributed to an insertion mutation in species Z, where an additional valine amino acid was inserted into the sequence.

Question 18

Answer the following questions in reference to the five items listed below.
-How many chromosomes are present in the somatic cells of a child born with Down syndrome (trisomy 21)?
A)12
B)23
C)24
D)46
E)47

Accepted Answer

A child born with Down syndrome (trisomy 21) has an extra copy of chromosome 21, resulting in a total of 47 chromosomes in their somatic cells (compared to the normal 46). Therefore, the correct answer is E, 47. Choices A, B, and C are incorrect as they have less than 46 chromosomes.

Question 19

Choose the most appropriate answer for each.
-monosomy
A)3n; generally sterile
B)a chromosome segment is permanently transferred to a nonhomologous chromosome
C)(2n - 1); a zygote deprived of a chromosome
D)a repeat of a particular DNA sequence in the same chromosome or in nonhomologous ones
E)(2n + 1); three chromosomes of the same kind are present in a set of chromosomes
F)a piece of the chromosome is inadvertently left out during the repair process
G)a chromosome segment that has been cut out and rejoined at the same place, but backward

Accepted Answer

Monosomy is a condition where a zygote is deprived of a chromosome, resulting in a diploid set of chromosomes with one missing.

Answer: E
 Trisomy is the condition where three chromosomes of the same kind are present in a set of chromosomes, resulting in a diploid set of chromosomes with one extra.

Answer: A
 Triploidy is a condition where there are three sets of chromosomes present, resulting in a 3n set of chromosomes, and often results in sterility.

The other answer choices do not describe monosomy.

Question 20

Answer the following questions in reference to the five items listed below.
-The normal sperm cell of species X carries 11 chromosomes.Following nondisjunction in the formation of secondary spermatocytes and their subsequent fertilization of normal ova,some of the zygotes will have 21 chromosomes,and the remainder will have how many chromosomes?
A)12
B)23
C)24
D)46
E)47

Accepted Answer

Nondisjunction in secondary spermatocytes leads to sperm with either an extra chromosome (12) or one less (10). Fertilizing a normal ovum (11 chromosomes) results in zygotes with either 23 or 21 chromosomes.

Quiz 14: Chromosomes and Human Inheritance

Answer the following questions in reference to the five items listed below. -Following a gene duplication event involving only five loci,how many chromosomes will a human female have?

Match the cause with the disorder. -Down syndrome

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement. -Homologous sets of genes ABCDEF and AEDCBF are located on homologous chromosomes.

Select the disorder that best matches each the following statements. -This disorder is an autosomal dominant disorder characterized by premature aging of body tissues.

Match the cause with the disorder. -albinism

Answer the following questions in reference to the five items listed below. -How many chromosomes are present in each cell of the germ cell line for a tetraploid species whose diploid complement of chromosomes is 48?

Match the cause with the disorder. -hemophilia A

Choose the most appropriate answer for each. -trisomy

Answer the following questions in reference to the five items listed below. -How many chromosomes does each somatic cell have in a human male who has two X chromosomes?

Choose the most appropriate answer for each. -triploidy

Select the best process listed below for each of the following statements. Note that you need to know that the sequence of amino acids directly reflects the sequence of genes that coded for their placement. -Homologous sets of genes ABCDEF and ABCDEF are located on nonhomologous chromosomes.

Match the cause with the disorder. -red-green color blindness

Match the cause with the disorder. -Turner syndrome

Answer the following questions in reference to the five items listed below. -How many chromosomes are present in the somatic cells of a child born with Down syndrome (trisomy 21) ?

Choose the most appropriate answer for each. -monosomy