Karyotyping I

Question 1

It is the number and appearance of chromosomes in the nucleus of a eukaryotic cell.

Answer 1

Karyotype

Question 2

[3] Karyotype analyzes:

Answer 2

1. Sex chromosomes
2. Presence or absence of individual chromosomes.
3. Nature or extent of chromosomal aberrations.

Question 3

It is a complete set of chromosomes in a species, or an individual organism.

Answer 3

Karyotype

Question 4

[2] Karyotypes may be performed by taking:

Answer 4

1. blood, bone marrow, or skin sample from adult.
2. sample of amniotic fluid or extra-embryonic cells from an unborn child.

Question 5

(contains stray cells)

Answer 5

amniotic fluid

Question 6

(from the chorionic villi)

Answer 6

extra-embryonic cells

Question 7

Once the cells have been obtained for a karyotype, they are mixed with plant-derived chemicals called ____ that stimulate mitosis.

Answer 7

lectins

Question 8

After the required quantity of cells has been acquired, the cells are treated with a drug called _____ to stop the mitotic process at metaphase.

Answer 8

colchicine

Question 9

This arrests the action of spindle fiber microtubules; hence ceasing the mitotic process.

Answer 9

Colchicine

Question 10

Chromosomes may be distinguished from one another based upon several key characteristics:

Answer 10

1. the length of the arms of the chromosome.
2. shape
3. general appearance of the chromosome.

Question 11

Provides a mechanism to determine if non-dis
junctional diseases, such as Down syndrome (Trisomy21), are present in the fetus.

Answer 11

Karyotype analysis

Question 12

It also provides a look at the chromosomes to see if there are any missing segments (deletions) or translocations that may have occurred during crossing-over.

Answer 12

Karyotype

Question 13

A chromosome number that is a multiple of the normal haploid set.

Answer 13

Polyploidy

Question 14

A chromosomal number that varies by something less than a set.

Answer 14

Aneuploidy

Question 15

Having three copies of a single chromosome.

Answer 15

Trisomy

Question 16

35%-70% of early embryonic deaths and spontaneous abortions are caused by this.

Answer 16

Aneuploidy

Question 17

1 in 170 live births are at least partially what?

Answer 17

aneuploid

Question 18

5%-7% of early childhood death stare related to?

Answer 18

Aneuploidy

Question 19

Errors in meiosis.

[poly, tri, tetra]

Answer 19

Polyploidy

Question 20

Events after fertilization.

[poly, tri, tetra]

Answer 20

Polyploidy

Question 21

Errors in mitosis.

[poly, tri, tetra]

Answer 21

Polyploidy

Question 22

Three sets of chromosome.

[poly, tri, tetra]

Answer 22

Triploidy

Question 23

Most common form of polyploidy.

[poly, tri, tetra]

Answer 23

Triploidy

Question 24

15%-18% of all spontaneous abortions.

[poly, tri, tetra]

Answer 24

Triploidy

Question 25

Approximately 75% have two sets of paternal chromosomes. [poly, tri, tetra]

Answer 25

Triploidy

Question 26

Probably due to polyspermy. [poly, tri, tetra]

Answer 26

Triploidy

Question 27

1% conceptions are triploid but 99% die before birth. [poly, tri, tetra]

Answer 27

Triplody

Question 28

Four sets of chromosome. [poly, tri, tetra]

Answer 28

Tetraploidy

Question 29

5% of all spontaneous abortions. [poly, tri, tetra]

Answer 29

Tetraploidy

Question 30

Extremely uncommon in live births. [poly, tri, tetra]

Answer 30

Tetraploidy

Question 31

May result from failure of cytokinesis in the first mitotic division. [poly, tri, tetra]

Answer 31

Tetraploidy

Question 32

Life threatening. [poly, tri, tetra]

Answer 32

Tetraploidy

Question 33

It is the failure of homologs or sister chromatids chromosomes to separate in meiosis or mitosis.

Answer 33

Non-disjunction

Question 34

[2] Non-disjunction

Answer 34

1. Produces abnormal gametes 2. Phenotypic effects of aneuploidy

Question 35

Lethal condition. [autosomal's]

Answer 35

Autosomal monosomy

Question 36

Aneuploidy during gamete formation produces equal numbers of monosomic and trisomic gametes and embryos. [autosomal's]

Answer 36

Autosomal monosomy

Question 37

Rarely seen in spontaneous abortions and live births. [autosomal's]

Answer 37

Autosomal monosomy

Question 38

Majority are lost early in development. [autosomal's]

Answer 38

Autosomal monosomy

Question 39

Most are lethal. [autosomal's]

Answer 39

Autosomal trisomy

Question 40

50% of cases of chromosomal abnormalities that cause fetal death are autosomal trisomies. [autosomal's]

Answer 40

Autosomal trisomy

Question 41

Trisomy 13

Answer 41

Patau syndrome (47 +13)

Question 42

Trisomy 18

Answer 42

Edward syndrome (47 + 18)

Question 43

Trisomy 21

Answer 43

Down syndrome (47 + 21)

Question 44

1/10,000 births [trisomy]

Answer 44

Edwards syndrome (47+18)

Question 45

Average survival time: 2-4 months [trisomy]

Answer 45

Edwards syndrome (47+18)

Question 46

Affected infants small at birth grow slowly and are mentally retarded. [trisomy]

Answer 46

Edwards syndrome (47+18)

Question 47

Malformation of heart, hands and feet. [trisomy]

Answer 47

Edwards syndrome (47+18)

Question 48

For unknown reasons 80% of all trisomy 18 are female. [trisomy]

Answer 48

Edwards (47+18)

Question 49

Advanced maternal age is a risk factor. [trisomy]

Answer 49

Edwards syndrome (47+18)

Question 50

1/5,000births. [trisomy]

Answer 50

Patau syndrome (47+13)

Question 51

Lethal: mean survival time is at least 1 month. [trisomy]

Answer 51

Patau syndrome (47+13)

Question 52

Facial malformations, eye defects, extra fingers or toes, and large protruding heels. [trisomy]

Answer 52

Patau syndrome (47+13)

Question 53

Severe malformations of brain, nervous system, and heart. [trisomy]

Answer 53

Patau syndrome (47+13)

Question 54

Parental age only known risk factor. [trisomy]

Answer 54

Patau syndrome (47+13)

Question 55

First chromosomal abnormality discovered in humans (1959). [trisomy]

Answer 55

Down syndrome (47+21)

Question 56

1/700 live births. [trisomy]

Answer 56

Down syndrome (47+21)

Question 57

Leading cause of mental retardation and heartdefects in US. [trisomy]

Answer 57

Down syndrome (47+21)

Question 58

Wide flat skulls, skin folds in the corner of the eyes, spots on the irises, and thick-furrowed tongues. [trisomy]

Answer 58

Down syndrome (47+21)

Question 59

40% congenital heart defects. [trisomy]

Answer 59

Down syndrome (47+21)

Question 60

Features do not develop until after puberty. [ktj syndrome]

Answer 60

Kinefelter's syndrome

Question 61

Affected individuals are male with low fertility and may have mental dysfunction. [ktj syndrome]

Answer 61

Kinefelter's syndrome

Question 62

60% due to maternal nondisjunction. [ktj syndrome]

Answer 62

Kinefelter's syndrome

Question 63

Other forms XXYY, XXXY and XXXXY. [ktj syndrome]

Answer 63

Kinefelter's syndrome

Question 64

Females; short, wide chest; rudimentary ovaries; and abnormal sexual development. [ktj syndrome]

Answer 64

Turner's syndrome

Question 65

Puffiness of hands and feet. [ktj syndrome]

Answer 65

Turner syndrome

Question 66

Abnormalities of the aorta. [ktj syndrome]

Answer 66

Turner syndrome

Question 67

No mental dysfunction. [ktj syndrome]

Answer 67

Turner syndrome

Question 68

Single X chromosome; two X chromosomes are required for normal female sexual development. [ktj syndrome]

Answer 68

Turner syndrome

Question 69

Complete absence of an X chromosome is lethal- (So, no Y monosomies). [ktj syndrome]

Answer 69

Turner syndrome

Question 70

Above average in height. [ktj syndrome]

Answer 70

Jacob syndrome

Question 71

No established link with possible antisocial behavior. [ktj syndrome]

Answer 71

Jacob syndrome