Lesson 4: Chromosome

Question 1

Primarily consist of DNA and protein

Answer 1

CHROMOSOMES

Question 2

Essential parts of chromosomes

Answer 2

■ Telomeres
■ Origins of replication sites
■ Centromere

Question 3

Largest constriction of the chromosome and where spindle fibers attach.

Answer 3

CENTROMERE

Question 4

Bases that form the centromere are
repeats of a ____.

Answer 4

171-base DNA sequence

Question 5

Centromere is replicated at the end of ____ and is facilitated by _____.

Answer 5

S shape
Centromere Protein A

Question 6

____ is the chromosome region between the centromere and telomeres.
Consists of ____ to ____ bases

Answer 6

SUBTELOMERE
8000 - 300,000

Question 7

Near telomere the repeats are
similar to the _____.

Answer 7

telomere sequence

Question 8

Contains at least ____ protein-encoding genes.
About __ are multigene families that include ____.

Answer 8

500
50%
pseudogenes

Question 9

● Chromosome chart.
● Major clinical tool.
● Displays chromosomes arranged by
___ and ___.

Answer 9

KARYOTYPE
size and structure

Question 10

Humans have __ chromosome types.
■ ____are numbered 1-22 by size
■ ____ are X
and Y

Answer 10

24
Autosomes
Sex chromosomes

Question 11

KARYOTYPE BENEFITS

Answer 11

● Confirm a clinical diagnosis.
● Reveal effects of environmental
toxins.
● Clarify evolutionary relationships.

Question 12

CENTROMERE POSITIONS

Answer 12

● Telocentric - At the tip.
● Acrocentric - Close to center.
● Submetacentric - Off-center.
● Metacentric - At center.

Question 13

VISUALIZING CHROMOSOMES:
Tissue is obtained from person, either:

Answer 13

Fetal tissue
Adult tissue

Question 14

fetal tissue includes:

Answer 14

■ Amniocentesis
■ Chorionic villi sampling
■ Fetal cell sorting
■ Chromosome microarray analysis

Question 15

Adult tissue:

Answer 15

■ White blood cells
■ Skin-like cells from cheek swab

Question 16

● Chromosomes are ___
● Then stained with a combination of
____ and _____

Answer 16

extracted
dyes and DNA probes

Question 17

Detects about 1000 of the more than
5000 known chromosomal and
biochemical problems.

Answer 17

AMNIOCENTESIS

Question 18

AMNIOCENTESIS detects about ____of the more than ____ known chromosomal and
biochemical problems.
● _____ is used to follow
needle’s movement.

Answer 18

1000
5000
Ultrasound

Question 19

In amniocentesis, the aim is to aspirate the ____ or suspended cells around the ___

Answer 19

fetal cells
fetus

Question 20

Performed during 10-12th week of
pregnancy

Answer 20

CHORIONIC VILLUS (villi) SAMPLING

Question 21

CHORIONIC VILLUS SAMPLING

● Performed during ____ week of
pregnancy.
● Provides _____ than
amniocentesis.
● Does not detect _____.
● Has greater risk of _____.

Answer 21

10-12th
earlier results
metabolic problems
spontaneous abortion

Question 22

_____, 1882
* Before the discovery of ___and _____, this is how chromosomes are detected

Answer 22

Walther Flemming
stains
fluorescence hybridization

Question 23

● DNA probes labeled with fluorescing
dye bind ____ DNA.
● _____ correspond to three
copies of chromosome 21.

Answer 23

complementary
Fluorescent dots

Question 24

abbreviation: 46, XY
meaning:

Answer 24

normal male

Question 25

abbreviation: 46, XX meaning:

Answer 25

normal female

Question 26

abbreviation: 45, X meaning:

Answer 26

turner syndrome (female)

Question 27

abbreviation: 47, XXY meaning:

Answer 27

klinefelter syndrome (male)

Question 28

abbreviation: 46, XY, del (7q) meaning:

Answer 28

male missing part of long arm (q) of chromosome 7

Question 29

abbreviation: 47, XX, +21 meaning:

Answer 29

female with trisomy 21 syndrome

Question 30

abbreviation: 48, XXYY meaning:

Answer 30

male with extra X and extra Y chromosome

Question 31

Schematic chromosome map

Answer 31

IDEOGRAM

Question 32

Indicates _____ (p or q) and major regions delineated by ____ patterns.

Answer 32

chromosome arms banding

Question 33

Karyotype may be abnormal in:

Answer 33

○ Chromosome number ○ Chromosome structure

Question 34

Abnormal chromosomes account for at least _____ of spontaneous abortions.

Answer 34

50%

Question 35

People are being diagnosed with _____ due to _____.

Answer 35

chromosomal abnormalities improved technology

Question 36

give the definition: -polyploidy -aneuploidy

Answer 36

extra chromosome sets an extra or missiong chromosome

Question 37

give the definition: -monosomy -trisomy

Answer 37

one chromosome absent one chromosome extra

Question 38

give the definition: -deletion -duplication

Answer 38

part of chromosome missing part of chromosome present twice

Question 39

give the definition: -translocation -inversion -isochromosome

Answer 39

2 chromosomes join long arms or exchange parts segment of chromosome reversed chromosome with identical arms

Question 40

give the definition: -ring chromosome -chromothripsis

Answer 40

chromosome that forms ring due to deletion one or more chromosome shatters

Question 41

_____ and _____ proved direct detection of _____.

Answer 41

Amniocentesis chorionic villus sampling extra chromosomes

Question 42

_____ offer an indirect method

Answer 42

Maternal serum markers

Question 43

Maternal serum markers offer an ____ method

Answer 43

indirect