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Flashcards in MCBG 16 Deck (40):
1

If you preform a haemoglobin electrophoresis, two bands appear. Why are 2 bands seen after performing
haemoglobin electrophoresis?

In a normal person there are two types of Haemoglobin in blood. HbA2 and HbA1

2

Why has thalassemia not be naturally selected (died out) ?

Being Heterzygous gives protection against malaria

3

What are reticulocytes?

immature RBCs - released in early response to anaemia

4

What is Lassitude??

lack of energy due to anoxia

5

What is anoxia??

The absense of oxygen

6

osteopenia?

Loss in bone mass

7

What is the major protein found in bone?

Collagen

8

Why is glycine present at every 3rd position
in the polypeptide chain?
1. Needed to make Hbonds
2. Small amino acid that fits
inside the helix
3. Hydrophilic side chain to
make interactions with
other chains
4. All of the above

2. Small amino acid that fits
inside the helix

9

What is the structure of Type I collagen? (chain type)

Two a1(I) and one a2(I)
chains

10

In gel electrophoresis, if one band twice as intense as
the other. What does that ?mean

Twice as much protein

11

What does the blue tinge in the sclera signify?

Osteogenesis imperfecta. A condition which is caused by a lack of type I collagen

12

What is cytogenetics?

Study of inheritance in relation to the structure and function of chromosomes.

13

What are the two Prenatal Diagnosis methods?

Chorionic Villus Sampling
Amniocentesis

14

What is Aneuploidy?

Loss or gain of a whole chromosome.

15

What is down syndrome characterised as?

An extra chromosome 21

16

What is Edwards characterised as (chromosome wise)?

Edwards +18

17

What is Polyploidy?

Gain of a whole haploid SET of chromosomes

18

Whats the difference between polyploidy and anuerploidy?

Polyploidy - Gain of a whole haploid SET of chromosomes (+23 haploid chromosomes)

Loss or gain of a (single) whole chromosome.

19

Types of polyploidy?

Diploid (normal number)
Triploid/triploidy (three lots of 23)
Tetraploid

20

What causes Aneuploidy?

1. Non-disjunction

21

What type of division causes mosacism?

Mitotic
Chromosomes can be “left-behind” at cell division because of defects in spindle
function or attachment to chromosomes

The lagging chromosome may be lost
entirely in mitosis or meiosis

22

.Whats Patau Syndrome?
Chromosome effect?
Effects (2)

Trisomy 13

Multiple congenital abnormalities
Polydactyly

23

Whats Turner syndrome?

Effects

45,X (female is missing an X)

Puffy feet,
redundant skin at back of neck

24

Whats the difference between mosaicism and chimerism?

Both are two different geneotypes within the same person. Mosaicism results from one person whereas Chimerism originates from different zygotes

25

Define chromosome translocation ?

Movement of Genetic Info from one chromosome to another

26

Define a balanced chromosome translocation ?

An even exchange of material with no genetic information extra or missing, and ideally full functionality

27

Define a unbalanced chromosome translocation ?

Unequal exchange of info

Get extra or missing genes

28

Why is it important to understand why translocation errors occurred in meiosis or mitosis?

MEIOSIS - problem with all of the mothers cells

MITOSIS - problem with just that cell line

29

Robertsonian Translocations

To acrocentric chromosomes fused together producing one big chromosome and one tiny tiny one. = 45 chromosomes

30

What does Acrocentric mean?

The p are is so small you cannot see it

31

Explain the steps in fish?

1) Get DNA probe (specific nucleotide sequence with labels or label attachments) and PCR it
2) De-nature DNA and add probe
3) MAGIC (aka hybridisation)
4) Wash unbound probe off
5) Visualise it using fluorescence microscopy

32

V.Important. Explain what tests FISH can be used for?
4

MORT
1. Mircodeletion syndromes
2. Identify chromosome of origin
3) Chromosome rearrangement/Translocation
4) Investigate telomeres

33

Name 4 different types of probes? (Think anatomy)

1. Locus/gene specific probes
2. Telomere probes
3. Centromere probes
4. Whole chromosome PAINTS

34

Whats the issue with using Locus specific probes on Microdeletion/duplication syndromes

Too small to see on G-banded chromosomes. (21,22, y)

35

Would you use a microarray for mutation detection

No

36

What are the two negatives of Microarrays? (hint in terms of chromosomes)

1) Can’t detect balanced rearrangements
2) Not used for mutation detection

37

Whats 45,X
effects?

Turners syndrome
Excess skin on back neck
swollen feet/hands at birth
Short statue

38

Whats XXX
effects?

Tiple X syndrome
Low IQ
Can have normal offspring

39

Whats XXY
effects?

Klinefelter Syndrome
More than one X for a male
Sterile
Weak muscle
Greater height
Small genitals
Breasts
Symptoms increase with more Xs

40

Whats XX Male
effects?

XX Male syndrome
Sry gene translocated on X chromosome