Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cell Biology II > Chapter 10 - Eukaryotic chromosome Abnormalities and organization > Flashcards

Chapter 10 - Eukaryotic chromosome Abnormalities and organization Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Process for creating a chromosome spread?

A

1 - sample white blood cels, treat with a solution to cause dividing

2 - use colchicine to disassemble microtubules,

3 - add to chambered slide in a hypotonic solution to cause swelling

4 - centrifuge cells, cells explode

5 - arrange chromo spread

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the FISH test?

A

Flourescent In-Situ hybridization
maps genetic material in human cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is g-banding

A
  • displays condensation levels of Euchromatin and heterochromatin in order to determine a deletion/duplication in genes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is euchromatin ?

A

transcriptionally active chromatin

displays a light stain on g-band test

decondenses in interphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is heterochromatin?

A

transcriptionally inactive chromatin
darker band
stays condensed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the types of heterochromatin?

A

Constitutive - areas of the chromosome that are always condensed
———-centromere: contins structural DNA, no genes, remains condensed
———–Telomere - remain condensed

Facultative - sometimes…
———-tissue specific and or developmental stage specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is euploid?

A

Euploid is having an equal number of copies of each gene on all chromosomes, even if this is not the wild type number

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is aneuploid, and what effect does it have on the gene dosage?

A

Unequal number of copies of each gene on all chromosomes

gene dosage is off… causes many problems

ex: trisome 13

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What causes aneuploidy?

A

Non disjunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Result of nondisjunction in meisos I?

A

all aneuploid ( trisomic, monosomic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

result of nondisjunction in Meiosis II?

A

50% aneuploid (25% trisomy, 25% mono)
50% euploid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Three examples of autosomal aneuploidy

A

trisomy 13 - patau syndrome
trisomy 18 - edward syndrome
trisomy 21 - down syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

four examples of sex-chromosome aneuploidies

A

47, XXY - klinefelter, M
47 XYY - jacob syndrome, M
47 XXX - triple X, F
45 XO - turner , F

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe mosaicism

A

Mosaicism is when 46, XX (wild type) experience non disjunction in meiosis, yielding 46 XX (wild type) and 45 XO/ 47 XXX, which are all included int he karyotype

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe uniparental disomy

A

Uniparental disomy is when both homologs are passed from one parent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how does a uniparental disomy occur

A

nondisjunction of the same chromosome in both sperm and egg

nondisjunction in one parent –> aneuploid gamete
———trisomy rescue

17
Q

what is a trisomy rescue?

A
  • one chromosome randomly gets kicked off
18
Q

What are the type of polypoidy?

A

autopolypoloidy - chromosomes from the same species (plants, sometimes we do on purpose (genetic modified food)

allopolyploidy - chromosomes from different species

19
Q

What determines if a species is fertile?

A

Even number of gametes = fertile
odd number = not fertile
ex: horse (64) x donkey (62) = mule (63)

20
Q

Describe a terminal deletion

A
  • partial deletion of a chromosome, lost in cell division
  • length missing depends on if organism is viable or not
21
Q

describe interstitial deletion

A
  • many small deletions within p or q arms
    -tests can be done to detect these deletions if symptoms arise
22
Q

Describe a duplication

A

extra genetic material

unpaired loops caused by chromosomes trying to line up and pushing duplicated portion out

23
Q

What does detection of a deletion/duplication look like in a FISH test?

A

Wild type - FISH probes A…(centro)…BC

Deletion - A…(centro)……C

duplication - A….(centromere)…BBC

24
Q

describe unequal crossing over?

A

1 - PMSa and PMSb misalign, a copy of PMS on each chromo loops out, unequal crossing occurs…

2 - recombinations:
deletion missing the 17 genes between PMS duplicates
duplication with PMS a and b, hybrid gene and duplication of the 17 genes

25
Q

Describe the two types of inversions?

A

a segment of chromosome is broken and rotates
Paracentric inversion - doesnt involve centromere

Pericentric inversion - does involve centromere

26
Q

How do inversions occur

A

1 - inversion loop occurs when chromosomes are trying to line up in meiosis

2 - there is a crossover between homologs, resulting in two viable gametes and two nonviable gametes (50% reduction in fertility)

27
Q

what are the three types of translocations?

A

unbalanced translocation

reciprocal balanced translocation

robertsonian translocation

28
Q

Describe unbalanced translocation

A

chromosome breakage occurs, translocated to a difference chromo… unbalanced sizes of chromosomes…

29
Q

describe reciprocal balanced translocation

A

there is an exchange in chromosome pieces, resulting in balances sizes of chromo

30
Q

describe robertsonian translocation

A

chromosome broken at centromere, p arm is lost and q arm is added to a normal chromosome.

31
Q

What is chromatin?

A

linear in shape, consists of DNA + Protein

DNA (coding/noncoding)
Protein(histone and nonhistone)

32
Q

What are the orders of packing

A

1 - 2 nm duplex (nucleosome, linker dna)
2 - 10 nm beads on a string (histone H1)
3 - 30 nm fiber, solenoid
4 - 300 nm chromatid…. looped chromatid, scaffold proteins
5 - 700 nm chromatid….. coiled chromo arm
6 - 1400 nm mitotic chromosome…. sister chromatids

33
Q

What is a histone protein?

A

consists of two tetramers… H2B, H2A, H3, H4

34
Q

How many base pairs of dna coil around a histone

A

146 bp

35
Q

What kind of replication is histone replication?

A

Semi conservative (partially old histones with newly synthesized histones)

36
Q

What is the position effect?

A

expression of a gene is influenced by where it is in the chromosome

37
Q

Describe the eye color phenomenon of the fly

A

1 - wild type: red eye color, W+ gene is expressed outside of the centromere, in a less compacted region
2 - variegated eye color: inversion moves W+ gene near the centromere, the gene is silenced when moved into heterochromatin which is more compacted, but expressed when outside the heterochromatin

Cell Biology II (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions