chapter 13

Question 1

euchromatin

Answer 1

parts of chromosomes that do not stain and that contain active genes

Question 1

comparitive genomic hybridization

Answer 1

a technique ysing fluorescent labels to detect small copy number variants

Question 2

aneuploid

Answer 2

a cell with one or more extra or missing chromosomes

Question 3

duolication

Answer 3

an extra copy of a DNA sequence, usually caused by misaligned pairing in meiosis

Question 4

cytogenetics

Answer 4

matching phenotypes to detectable chromosomal abnormalities

Question 5

chromothripsis

Answer 5

shattering of chromosomes

Question 6

euploid

Answer 6

a somatic cell with the typical number of chromosomes for the species

Question 7

heterochromatin

Answer 7

dark staining chromosome parts that have few protein-encoding genes

Question 8

isochromosome

Answer 8

a chromosome that has two copies of one arm but none of the other, as a result of cell devision along the wrong plane

Question 9

metacentric

Answer 9

a chromosome with a centromere that divides it into two arms of approximately equal length

Question 10

microdeletion

Answer 10

a very small chromosomal deletion (missing part); a type of copy number bariant

Question 11

microduplication

Answer 11

a very small second copy of a DNA sequence; a type of copy number variant

Question 12

monosomy

Answer 12

a cell missing a chromosome; in humans, a cell with 45 chromosomes

Question 13

nondisjunction

Answer 13

unequal distribution of chromosomes during meiosis

Question 14

paracentric inversion

Answer 14

a chromosomal inversion in which the inverted section does not include the centromere

Question 15

pericentric inversion

Answer 15

a chromosomal inversion in which the inverted part includes the centromere

Question 16

reciprocal translocation

Answer 16

a chromosome in which two nonhomologous chromosomes exchange parts, conserving genetic balance but rearranging genes

Question 17

robertsonian translocation

Answer 17

a chromosome in which two short arms of nonhomologous chromosomes break off and are lost and the long arms fuse, one unusual, large chromosome forms

Question 18

structural variant

Answer 18

a deleted, inverted, duplicated, or moved section of a chromosome that exceeds 1k bases

Question 19

submetacentric

Answer 19

a chromosome in which the centromere position establishes a long arms and a short arm

Question 20

translocation carrier

Answer 20

an individual with a large, translocated chromosome who may not have any symptoms. The genetic material is rearranged

Question 21

translocation

Answer 21

exchange of genetic material between nonhomologous chromosomes or a piece of one chromosome being moved to another

Question 22

trisomy

Answer 22

a human cell with one extra chromosome, for a total of 47

Question 23

uniparental disomy

Answer 23

inheriting two chromosomes or chromosome segments from one parent

Question 24

what is heterochromatin made of

Answer 24

repetitive sequences and the centromere or telomere

Question 25

when is chorionic villus sampling done

Answer 25

10-12th week

Question 26

what do we use to ciew chromosomes

Answer 26

electron micrograph Fluorescence in Situ Hybridization

Question 27

what is 47 XXY

Answer 27

klinefelter syndrome

Question 28

what is 45 X

Answer 28

turner syndrome

Question 29

what is 47 XYY

Answer 29

jacobs syndrome

Question 30

what is 47 XX and +21 trisomy

Answer 30

down syndrome

Question 31

how does triploid happen

Answer 31

extra set of all chromosomes from feetilization of one egg by two sperm

Question 32

nondisjunction at meiosis I

Answer 32

() (XX) meiosis II is () () (x) (x)

Question 33

nondisjunction at meiosis Ii

Answer 33

(x)(x) (>)(<) () (X) fertilization means 2 euploid 1 monosomic and 1 trisomic

Question 34

which trisomy is most common

Answer 34

21 down syndrome

Question 35

what does turner syndrome do

Answer 35

one X so developmental problems

Question 36

what is triple X syndrome

Answer 36

tall irregular menstrual cycle and slightly less jntelligent

Question 37

what does klinefelter syndrome do

Answer 37

incomplete sexual development large testes and prostate long limbs breadt tissue infertility

Question 38

what does XXYY dynrome do

Answer 38

severe behavioral problems

Question 39

what does jacobs syndrome do

Answer 39

great height acne and speech disabilities

Question 40

subtelomeres

Answer 40

between centromeres and telomeres

Question 41

acrocentric

Answer 41

small material on one end

Question 42

are chorionic villi and fertilized ovum the same content

Answer 42

no and this causes false negatives and positives

Question 43

atypical chromosomes account for

Answer 43

%50 of abortions

Question 44

atypical chromosomes account for

Answer 44

%50 of abortions

Question 45

what is aneuploidy caused by

Answer 45

nondisjunction

Question 46

what causes trisomy 18

Answer 46

nondisnjuction in meiosis II

Question 47

what is trisomy 18

Answer 47

edwards syndrome

Question 48

what is trisomy 13

Answer 48

patau syndrome