Chapter 8

Question 1

additional copies of a gene ___ cause cellular problems

Answer 1

sometimes

Question 2

the spread of a complete metaphase chromosome set presented for diagnostic purposes is called a ___.

Answer 2

karyotype

Question 3

failure to separate for homologous chromosomes or sister chromatids is referred to as ____.

Answer 3

nondisjunction

Question 4

of all cases of primary Down syndrome, 92% is due to ____ of chromosome 21

Answer 4

trisomy

Question 5

which statement about chromosome inversions is correct?

Answer 5

chromosome inversions flip a segment of a chromosome 180 degrees

Question 6

which statement about aneuploidy is true?

Answer 6

one form of aneuploidy is a loss of both members of a homologous pair of chromosomes

Question 7

which statement about down syndrome is true ?

Answer 7

trisomy of chromosome 21 is well tolerated enough to give rise to fully-developed individuals

Question 8

during meiosis, erros occur durring chromosome replication

which term describes the rearranging of genetic material between non homologous chromosomes without a net loss or gain of genetic material

Answer 8

translocation

Question 9

AB. CDEFG> AB. CFEDG

which type of inversion is presented ?

Answer 9

paracentric

Question 10

which structure forms as a result of a crossover between two paired chromatids in which one chromatid has the normal gene order and the other has a paracentric inversion?

Answer 10

dicentric bridge

Question 11

which term describes the process of sister chromatids not separating at the centromere during cell division?

Answer 11

nondisjunction

Question 12

match the definitions to the appropriate terms that describe the number of chromosomes
haploid
monosomic
n=1

Answer 12

haploid: a single unpaired copy of each chromosome
monosomic: only one copy of a specific chromosome
n=1 : a genome composed of one unique chromosome

Question 13

define euploidy

Answer 13

a complete chromosome set or an exact multiple of the haploid chromosome set

Question 14

patient 367 karyotype missing an entire X chromosome also known as Turner syndrome (XO syndrome)

which form of aneuploidy is this?

Answer 14

monosomy

Question 15

two brothers have X-linked red-green colorblind vision, and their parents have normal color vision. the first brothers karyotype is 47, XXY (Klinefelter syndrome) , and the second brothers karyotype is 46, XY

in which parent and in what cell division phase did the first brothers chromosomal nondisjunction occur? assume no recombination.

Answer 15

in the mother in meiosis II

Question 16

red- green color blindness is a human X-linked recessive disorder. the normal allele XB is dominant to the mutant allele Xb. Jill has normal color vision, but her father is color blind. Jill marries tom who also has normal color vision. Jill and tom have a daughter who has Turner syndrome and is color blind.

how and from whom did the daughter inherit color blindness?

Answer 16

an ovum carrying Xb followed by fertilization by sperm from a paternal nondisjunction event

Question 17

frank has Klinefelter syndrome (47, XXY). his mother has normal skin, but his father has anhidrotic ectodermal dysplasia, an x-linked condition where the skin does not contain sweat glands. frank has patches of normal skin without sweat glands.

frank received the mutant chromosome from his ___.
nondisjunction occurred in his ____ during the ____ meiotic division.

Answer 17

father
father
first