Brainscape's Knowledge GenomeTM

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


See full index

MCBM EXAM 4 > Mutations & Repair + Mendelian Genetics > Flashcards

Mutations & Repair + Mendelian Genetics Flashcards

1
Q

Mutations affect the only copy of the genetic information available.
(Prokaryotes/Eukaryotes)

A

Prokaryotes

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

Mutations in _____ cells of Eukaryotes can be inherited.

A

Germ cells

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

Mutations in ______ cells are not inherited and affect tissues only.

A

Somatic cells

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

Cancer in a ____ mutation. (germ cell/somatic cell)

A

Somatic cell

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

Mutations in germ cells that predispose to cancer can be inherited. (T/F)

A

True

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

Germline mutations give rise to ______ mutation in offspring.

A

Constitutional

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

what does constitutional mutation mean?

A
  • Every cell of that offspring will carry the mutation.

- If happens very early in cleavage stages, results in mosaic mutation.

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

Somatic mutation will only be harmful if:

A

they result in a substantial clone of mutant cells.

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

Name the major types of mutation/

A
  1. Substitution
  2. Deletion
  3. Insertion
  4. Rearrangement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Name the types of substitution mutation.

A
  • Transition: py for py
  • Transversion: py for pur OR pur for py
  • Nonsense: make a stop codon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 4 causes of mutation?

A
  1. Errors during DNA replication.
  2. Chemical modification.
  3. Intercalation.
  4. Double-strand breakage.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Errors during DNA replication result in:

A

Tautomer formation.

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

Intercalation can result in:

A

Insertion or deletion

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

Double-strand breakage can result in:

A

Deletions

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

Name three intercalators.

A
  • Ethidium
  • Bromide
  • Acridine orange
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name 2 chemical modifiers.

A
  • Nitrous acid

- alkylating agents

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

Chemical modification can cause what mutations?

A
  • Transitions
  • Transversions
  • Frameshifts
  • DNA repair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Radiation exposure (UV/X-rays) cause what type of mutation?

A
  • DS breakage

- Thymine dimers

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

Generally, mutation repair system have these steps:

A
  1. Detect
  2. Remove
  3. Repair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Mismatch repair “detect” enzyme:

A

-Dam methylase

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

Mismatch repair “remove” enzyme:

A

-Exonuclease I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Mismatch repair “repair” enzymes:

A
  • DNA polymerase III

- DNA ligase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Base-excision repair “detect” enzyme:

A

DNA glycosylases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Base-excision repair “remove” enzyme:

A

AP endonucleases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Base-excision repair “repair: enzymes:

A
  • DNA polymerase I

- DNA ligase

26
Q

How is the correct strand chosen during mismatch repair?

A

Strand with error is unmethylated

27
Q

Defects in human mismatch repair system lead to a strong predisposition to:

A

Hereditary nonpolyposis colorectal cancer

28
Q

Nucleotide Excision Repair is used for:

A

bulky distortions of DNA helix.

e.g., thymine dimers

29
Q

Thymine dimers are caused by:

A

UV radiation exposure

30
Q

What enzyme cleaves the defected DNA in E. coli during nucleotide excision repair?

A

ABC exinuclease

31
Q

Defects of the human thymine dimer system leads to:

A

Xeroderma pigmentosum

32
Q

Symptoms of XP:

A
  • UV sensitivity
  • keratoses
  • scaring of the eyelids
  • cornea ulceration
  • multiple skin tumors
  • many pts die before 30
33
Q

Define genotype.

A

The genetic constitution of an individual

34
Q

Define phenotype.

A

The observable expression of a genotype as a morphological, biochemical, or molecular trait.

35
Q

In autosomal dominant disorders, _______ are phenotypically affected.

A

Heterozygotes

36
Q

Inheritance pattern for hypercholesterolemia is:

A

Autosomal dominant.

37
Q

Name the two variations of hypercholesterolemia.

A
  • Xanthelasmus

- Corneal arcus

38
Q

Xanthelasmus is AD heterozygous/homozygous.

A

Heterozygous

39
Q

Homozygous variation of hypercholesterolemia is called:

A

Corneal arcus

40
Q

What are the symptoms of xanthelasmus?

A

Achilles tendon xanthomas

41
Q

Metacarpophalangeal tendon xanthomas is associated with this Dz.

A

Corneal arcus

42
Q

Corneal arcus is the homozygous/heterozygous variation of hypercholesterolemia.

A

Homozygous

43
Q

In Autosomal Dominant pedigree, ____ % of the offsprings have the Dz.

A

50

44
Q

Huntington’s chorea inheritance pattern is:

A

Autosomal Dominant

45
Q

What are the exceptions to the Autosomal Dominant inheritance pattern?

A
  1. New mutation in gamete of phenotypically normal parent.
  2. Variable penetrance.
  3. Variable expressivity.
46
Q

How do the exceptions to the autosomal dominant inheritance affect the pattern?

A

They mask the presence of the mutant genotype in the parental phenotype.

47
Q

In Autosomal Recessive inheritance, only _______ are phenotypically affected.

A

homozygotes

48
Q

Male and females are equally affected in autosomal recessive inheritance. (T/F)

A

True

49
Q

What is the % chance recurrence risk for each sibling in autosomal recessive inheritance?

A

25%

50
Q

Examples of Autosomal Recessive Dz:

A
  • Cystic fibrosis
  • Sickle cell anemia
  • Tay-Sachs Dz
  • PKU
51
Q

Cystic fibrosis is an AD/AR Dz.

A

AR

52
Q

“Mother to son” transmission is this inheritance pattern.

A

X-linked Recessive

53
Q

Male and female phynotypes are equally affected in X-linked Recessive inheritance. (T/F)

A

False; Incidence of phenotype is much higher in males than females.

54
Q

In X-linked recessive Dz, mutant gene is transmitted from father to:

A

ALL daughters

NO sons

55
Q

What is a manifesting heterozygote?

A

Heterozygous females are usually unaffected by X-linked recessive inheritance but may show some variable expression of the trait.

56
Q

Define The Lyon Hypothesis.

A
  • All females are mosaics with respect to X.

- Inactivated X chromosomes are called Barr bodies.

57
Q

Inactivated X chromosomes are called:

A

Barr bodies.

58
Q

Hemophilia A inheritance pattern:

A

X-linked Recessive

59
Q

Mitochondrial disorders are purely _____ inheritance.

A

maternal

mother to everybody!

60
Q

Sons and daughters are equally affected in mitochondrial disorders. (T/F)

A

True

MCBM EXAM 4 (9 decks)

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