Brainscape's Knowledge GenomeTM

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


See full index

BCMB > Week 5 > Flashcards

Week 5 Flashcards

1
Q

mutation

A

change in genetic material. Can be spontaneous or induced

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

Germline mutation

A

mutation in gamete cells so the mutation is heritable.

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

Somatic mutations

A

mutation in nonreproductive cells. Usually isolated to the individual

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

induced mutations

A

are more common. Caused by mutagens or chemical/physical agents, radiation

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

How do mutagens disrupt pairing?

A

By modifying nucleotide structure

using base analogue similar to particular bases

by using Alkylating agents to create numerous DNA lesions

including interstrand cross-links.

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

How do mutagens interfere with replication?

A

by intercalating or inserting between bases and distort the helix

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

point mutations

A

affects only a single base pair

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

Missense

A

change in amino acid encoded

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

Frameshift mutation

A

shifts triplet reading of codons out of correct phase

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

Silent mutation

A

no change in amino acid encoded

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

deletion mutation

A

one or more missing nucleotides

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

Insertion mutation

A

One or more extra nucleotides present

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

Transversion mutation

A

purine to pyrimidine, or pyrimidine to purine

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

Transition mutation

A

Pyrimidine to pyrimidine, or purine to purine

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

Nucleotide substitution

A

one base pair in duplex DNA replaced with a different base pair

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

Gain of function mutation

A

expressed at incorrect time or in inappropriate cell types

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Hypermorphic mutation

A

increases normal function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Spontaneous mutation

A

they occur in the absence of any known cause

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

conditional mutation

A

Expressed only under restrictive conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

unconditional mutation

A

Expressed under permissive conditions as well as restrictive conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Hypomorphic mutation

A

reduces normal function

22
Q

Loss of function mutation

A

eliminates normal function

23
Q

nonsense mutation

A

creates translational termination codon

24
Q

DNA repair requirements

A

DNA damage be detected and repair of DNA damage

25
Q

Direct repair

A

Can reverse some damage i.e. UV damage

26
Q

Excision repair

A

Altered DNA strand is removed and new segment synthesized “sledge hammer and duct tape”

27
Q

Global nucleotide excision Repair

A

repair recognizes lessons anywhere in the genome

28
Q

transcription-coupled nucleotide excision repair

A

preferentially repairs the transcribed strand of active genes

29
Q

mismatch repair

A

 A type of excision repair, it entails first the removal of the mismatched base pairs, then a replacement with the correct base pairs.  The mismatch repair system preferentially corrects the base in the daughter strand following replication fork passage.  MutH, MutS, and MutL proteins No specific sequence needed for it to find where to cut. The shape of the DNA is the indicator that there is something wrong

30
Q

Base excision repair

A

removes bases damaged by oxidation, alkylation, and deamination.  The damaged base is directly removed from the DNA • Glycosylase: breaks the covalent bond btwn the damaged base and the DNA strand  Base removal triggers the excision and replacement of a stretch of DNA  Abasic sites are repaired through this mechanism, with the exception of the first step: base excision • Base is already absent

31
Q

Double strand breaks repair

A

repaired by 2 major pathways: Homologous recombination & non-homologous end joining (NHEJ)

32
Q

Homologous recombination

A

occurs in meiosis to mix genes from maternal and paternal chromosomes before separating to form gametes o Depends on the presence of a homologous donor sequence that can be used to accurately replace sequences that may have been lost in the breakage

33
Q

Non-homologous end joining

A

o When no homologous donor sequences are available, NHEJ is engaged. o Involves directly ligating ends of DNA strands o High risk of completely losing certain sequences prior to repair

34
Q

Possible effects of repairing double stranded breaks

A

how the damage is repaired can sometimes lead to chromosome problems: • Deletions, inversions, translocations, chromosome-chromosome fusions, etc.

35
Q

How will a double stranded break not have a deleterious effect?

A

 In order for a double stranded break to not have a deleterious effect, it must not occur in a coding region, nor in a regulatory region, and it must have a homologous donor available (sister chromatid).

36
Q

Chromosomal abnormalities

A

Frequently, chromosomal abnormalities are the result of breaks and subsequent repair events in critical regions of the genome

  • Have their own short hand
  • Can be numerical & structural
37
Q

chromosome nomenclature

A
  • Arms (sections on either side of the centromere) are defined as petite (p) or grande (q) • long (q) and short (p)
  • Regions are numbered starting from the centrom ere and moving outward
  • The bands in each region are numbered (again, moving outward from the centromere
38
Q

Naming a chromsome

A

starts with the chromosome numbers, arm (p/q), region, and band

39
Q

autosomes

A

chromosomes 1-22

40
Q

Anatomy of a chromosome

A
41
Q

Numerical (Anueploidy)

A

can be caused by a non-disjunction in Meiosis I or II. Polyploidy or Monosomy

42
Q

polyploidy

A

more than 2 of any chromosomes

I.e. Trisomy 21 = Down Syndrome

43
Q

Monosomy

A

Only 1 copy of a chromosome

i.e. Turner Syndrome: XO

44
Q

Chromosome abnormality: Reciprocal

A
  • Breakage of at least 2 chromosomes and exchange of the fragments
  • Usually no deleterious effects in the carrier
  • Issues arise during chromosome segregation in meiosis I
    • Cannot form bivalents due to translocation
    • Instead, form a complex called a pachytene quadrivalent
    • Segregation pattern of the quadrivalent will determine how deleterious the effect will be for each resultant gamete
45
Q

chromosome abnormality: Robertsonian

A
  • Breakage of 2 acrocentric chromosomes near the centromere, and fusion of their long arms
  • Also called ‘centric fusion’
  • Short arms are lost
  • Functionally is a balanced rearrangement
  • Issues arise during chromosome segregation in meiosis I
46
Q

chromosome abnormalities: deletions

A

Loss of part of a chromosome, resulting in monosomy for that portionof the chromosome

Duchenne muscular dystrophy: delXp21

47
Q

Chromosomal abnormalities: insertions

A

Segment of one chromosome becomes inserted into another chromosome

If inserted material has moved from elsewhere in another chromosome then the karyotype is balanced

If material is duplicated within same chromosome compliment it is unbalanced

48
Q

chromosomal abnormality: Mixoploidy

A

describes when there are 2 groups of cells in a single individual, each with a unique genetic makeup

49
Q

mosaicism

A

You have a normal zygote and there’s a non-disjunction in one of the mitiotic divisions down the road

50
Q

Chimerism

A

2 Single egg and single sperm combos fuse into one big blastula can form a chimera

Very rare

BCMB (8 decks)

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