Brainscape's Knowledge GenomeTM

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


See full index

Molecular Biology & Medical Genetics > Week 2 > Flashcards

Week 2 Flashcards

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

When calculating the frequency of alleles, the number (n) of homozygous (AA) or heterozygous (Aa) samples must be doubled before dividing by 2N?

A

Homozygous (AA)

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

In a dominant gene disease, which allele is pathogenic, d or D?

A

D

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

What is the typical recurrence risk for an Autosomal Dominant disease?

A

50%

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

In the Hardy-Weinberg Law formula: p2 + 2pq + q2 = 1 , what does the p2 represent in terms of alleles?

A

Frequency of AA

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

If some people with a mutation of a gene do not develop the features of the disorder, the condition is said to have:

A

A reduced penetrance

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

Tay Sachs Disease:

Autosomal Dominant, or Recessive?

A

Autosomal Recessive

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

Traits occuring in only one sex due to anatomical differences are classified as:

Sex-limited Traits,

or

Sex-Influenced Traits?

A

Sex-Limited Traits

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

Sickle Cell Anaemia:

Autosomal Dominant, or Recessive?

A

Autosomal Recessive

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

A disorder affecting chromosome 11 causes upregulation of growth factor, is this disease:

Beckwith-Weidemann Syndrome

or

Silver-Russel Syndrome?

A

Beckwith-Weidemann Syndrome

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

What is the function of Xist RNA?

A

Inactivation of X Chromosomes

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

Why do females display a lower severity of symptoms in Fragile X Syndrome than males?

A

Females have two copies of the X chromosome, one may be a normal copy

(Females are mosaic)

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

“Common in Ashkenazi Jews and French Canadian peoples.”

Is this a feature of Sickle Cell anaemia, or Tay Sachs disease?

A

Tay Sachs Disease

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

What is the purpose of maintenance methylation?

A

methylating newly synthesised strands of DNA

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

25% of cases of Prader-Willi syndrome are caused by uniparental disomy of chromosome 15 - what does this mean?

A

The child inherits both copies of Chromosome 15 from the same parent

(Maternal in this case)

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

The Angelman Syndrome gene on chromosome 15 is active, or inactive in paternal chromosomes?

A

Inactive

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

Why will uniparental disomy of chromosome 15 cause either Prader-Willi or Angelman Syndrome?

A

Active and Inactive PWS and AS regions are sex-dependant

(Maternal or Paternal)

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

What does Wild Type refer to in protein synthesis?

A

Proteins produced by healthy genes before any mutation

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

Chronic Myelogenous Leukaemia results from translocation of most of chromosome 22 on to the long arm of chromosome 9 in haematopoetic stem cells, what is this new hybrid chromosome known as?

A

The Philadelphia Chromosome

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

Two non-homologous acrocentric chromosomes loose their short arms (P), and the residual long arms (Q) fuse to form one long chromosome - what is this phenomenon refererred to as?

A

Robertsonian Translocation

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

In the Hardy-Weinberg Law formula: p2 + 2pq + q2 = 1 , what does the q2 represent in terms of alleles?

A

Frequency of aa

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

The probability that the child of a patient may inherit a particular disease is known as:

A

Recurrence Risk

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

Females are considered genetic mosaics with regard to X-Linked genetic traits - what does this mean?

A

She will express X-linked alleles from both her mother and her father

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is Pleitropy?

A

single genes having more than one discernible effect on the body

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

A mutation in a trinucleotide results in the replacement of Leucine with Proline - is this a nonsense or a missense mutation?

A

Missense mutation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The Prader-Willi gene on chromosome 15 is active, or inactive in maternal chromosomes?

A

Inactive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The probability of a child having a genetically inherited disease is proportional to the number of siblings they have.

True

or

False?

A

False.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

With relation to chromosome 15, by what three mechanisms will a patient develop either Prader-Willi Syndrome or Angelman Syndrome?

A

Uniparental disomy

Defective imprinting

Deletion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the three forms of Tay-Sachs disease?

A

Infantile

Juvenile

Adult/Late

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

X linked dominant diseases passed down from the mother are seen in boys, girls, or both?

A

Both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

A law states* that genotype and allele frequencies will always remain constant from generation to generation - what is this law?

*provided certain criteria are met

A

Hardy-Weinberg Law

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Swyer Syndrome results from an error in the SRY / SOX9 crossover process, does this result in an XX Male, or an XY Female?

A

XY Female

Also Known as XY Gonadal Dysgenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

In the Hardy-Weinberg Law formula: p2 + 2pq + q2 = 1 , what does the 2pq represent in terms of alleles?

A

Frequency of the Aa combination

34
Q

What is the phenomenon that describes defective genes in different chromosomes causing the same disease?

A

Locus Heterogeneity

35
Q

What is the name of the deactivated X chromosomes in the cells of women?

A

Barr bodies

36
Q

Genetic conditions such as Marfan’s Syndrome with a spectrum of mild to severe features is conisdered to have:

A

Variable Expressivity

37
Q

A mutation in a trinucleotide encoding the translation of alanine results in no change to the amino acid sequence, was this a misense or a silent mutation?

A

Silent Mutation

38
Q

A male inheriting an X-Linked dominant disease would have gained the allele from the mother or the father?

A

Mother

39
Q

What is the typical recurrence risk of an autosomal dominant disease?

A

50%

40
Q

What aspect of pedigree should be considered when a rare recessive disease is discovered?

A

Cosanguinity

41
Q

Is Male Pattern Baldness a Sex-Limited trait, or a Sex-Influenced trait?

A

Sex-Influenced Trait

42
Q

Myotonic Dystrophy is an autosomal dominant, or recessive disease?

A

Autosomal Dominant

43
Q

is X-Linked Dominant disease transmission possible between fathers and sons?

A

No

44
Q

What is the typical recurrence risk for an Autosomal Recessive disease?

A

25%

45
Q

In X-Linked Recessive diseases, why is maternal transmission of disease always expressed in sons?

A

Males do not have a compensatory allele for the affected X-Chromosome gene

46
Q

during the second stage of gene silencing, Histone Deacetylase (HDAC) binds to both:

A

MeCP and DNA

47
Q

Albinism:

Autosomal dominant, or recessive?

A

Autosomal Recessive

48
Q

Father to son transmission of genetic disease is an attribute of Autosomal Dominant, or Autosomal Recessive?

A

Autosomal Dominant

49
Q

De La Chapelle Syndrome results from an error in the SRY / SOX9 crossover process - Does this result in an XX Male, or an XY Female?

A

XX Male

50
Q

Methylation upregulates or downregulates gene expression?

A

downregulates

51
Q

is Methylcytosine-binding protein (MeCP) the first or second molecule used in gene silencing?

A

First

52
Q

Anticipation of genetic disease (Progresive worsening between generations) is caused by what?

A

Trinucleotide Repeat Expansion mutation

53
Q

Robertsonian Translocation occurs between two Homologous or Non-Homologous pairs of chromosomes?

A

Non-homologous

54
Q

Both alleles affecting the phenotype are a feature of what type of inheritance?

A

Codominant Inheritance

55
Q

A new gene formed at the interface between two translocated chromosome is known as:

A

An Oncogene

56
Q

how many generations are required to be examined to qualify a ‘complete’ history, regarding genetic disease?

A

Three

57
Q

What do geneticists mean by anticipation?

A

Severity of the disease and earliness of onset increases as the disorder is passed from one generation to the next

58
Q

What is the most important factor in calculating recurrence risk?

A

How the disease is inherited

59
Q

What is the most straightforward method of epigenetic control?

A

DNA Methylation

60
Q

The Angelman Syndrome gene on chromosome 15 is active, or inactive in maternal chromosomes?

A

Active

61
Q

Is mitochondrial inheritance maternal, or paternal?

A

Maternal

62
Q

The Prader-Willi gene on chromosome 15 is active, or inactive in paternal chromosomes?

A

Active

63
Q

Cri-du-chat Syndrome is a resut of a deletion or a translocation of chromosome 5?

A

Deleted

64
Q

What is the typical recurrence risk of an autosomal recessive disease?

A

25%

65
Q

What does Haploinsufficient mean?

A

Affected genes do not produce enough proteins to fulfil their designated function

66
Q

During methylation, which enzyme adds the first methyl group?

de novo methylase

or

Maintenance methylase

A

de novo methylase

67
Q

How many of the parents must be carriers of the defective gene in order for one of their offspring to express an autosomal recessive disease?

A

Both

68
Q

Familial Isolated Growth Hormone Deficiency (IGHD) is an example of complex genetic transmission, why?

A

There can be both recessive and dominant IGHD

69
Q

What is the purpose of the methylated CG-Islands in DNA methylation?

A

Interfering with DNA transcriptase activity

70
Q

Chromosomes of what morphology may be subject to Robertsonian Translocation?

A

Acrocentric

71
Q

The process of forming Barr Bodies with Xist RNA is known as:

A

Lyonisation

72
Q

Robertsonian Translocation occurs during:

Gametogenesis

or

Embryonic Cell Division?

A

Gametogenesis

73
Q

Fragile X Syndrome is typically more severe in males, or females?

A

Males

74
Q

A disorder affecting chromosome 11 causes downregulation of growth factor, is this disease:

Beckwith-Weidemann Syndrome

or

Silver-Russel Syndrome?

A

Silver-Russel Syndrome

75
Q

“Common in Africans, African Americans and Mediterranian peoples.”

Is this a feature of Sickle Cell anaemia, or Tay Sachs disease?

A

Sickle Cell anaemia

76
Q

In a recessive gene disease, which allele is pathogenic, d or D?

A

d

77
Q

What does Haplosufficient mean?

A

Accounting for any mutation, there are sufficient proteins produced to maintain homeostatic function

78
Q

During the first stage of gene silencing, what molecule is attracted to the methylated CG-Islands?

A

Methylcytosine-binding protein (MeCP)

79
Q

Where is the site of original de-novo mutation in Germline Mosaicism?

A

The embryo

80
Q

De novo methylase adds methyl (CH3) groups to what locations on the DNA molecule?

A

CG Islands

81
Q

What are the two forms of Huntington’s Disease?

A

Adult Onset

Juvenile Onset

Molecular Biology & Medical Genetics (5 decks)

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