Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Principles of Disease > Chromosomes > Flashcards

Chromosomes Flashcards

(77 cards)

Start Studying
1
Q

What is G1 of the cell cycle?

A

The first growth phase

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

What is G2 in the cell cycle?

A

The second growth phase

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

What occurs at the S phase of the cell cycle?

A

DNA Replication

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

What is the M phase of the cell cycle?

A

The mitotic phase

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

How long does the mitotic phase of the cell cycle last?

A

1-2 hours

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

What happens at prophase of mitosis?

A

Chromosomes condense
Nucelar membranes disappear
Spindle fibres form from the centriole

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

What happens at metaphase of mitosis?

A

Chromosomes aligned at the equator of the cell
Attatched by fibre to each centriole
Maximum condensation of chromosome

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

What happens at anaphase of mitosis?

A

Sister chromatids separate at centromere
Separate longitudinally
Move to opposite ends of the cell

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

What happens at telophase of mitosis?

A

New nuclear membranes form

Each cell contains 46 chromosomes (diploid)

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

Cytokinesis

A

Cytoplasm separates

Two new daughter cells are formed

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

What is the centromere?

A

The constricted region joining sister chromatids

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

Where is the site of the kinetochore?

A

The centromere

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

What is the kinetochore?

A

Protein complex that binds to microtubules

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

What are required for chromosome separation during cell division?

A

Microtubules

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

What are heterochromatin?

A

Condensed structure

These are the silenced genes

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

What are euchromatin?

A

They are open structures

They are the active genes

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

How many base pairs are there?

A

3 million

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

How many genes are there roughly in DNA?

A

20000-30000

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

What percentage of DNA is protein coding?

A

2%

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

What proteins is SNA packaged with?

A

Histone

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

What charge do histone proteins carry?

A

Positive

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

DNA packaged around histone proteins are units called what?

A

Nucleosomes

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

What appearance does DNA wrapped around histones give?

A

Beads on a string

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

Nucleosomes are further wrapped how many times?

A

6 nucleosomes per turn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What do 6 nucleosomes wrapped form?
Solenoid structure
26
What effect does the histone proteins have on the charge of DNA?
The negatively charged DNA is neutralised by the positively charged histone proteins
27
Why is DNA folded so much?
So it takes up less space and can be compacted into the small nucleus
28
What is karyotype?
A test to identify and evaluate the size, shape and number of chromosomes in sample of the bodies cells
29
In what cells does meiosis occur?
Germ Cells
30
What is the purpose of meiosis?
To create a lot of genetic variation
31
In which diploid cells does meiosis occur?
Ovaries and testes
32
What is oogenesis?
The process of egg formation
33
What is spermatogenesis?
The process of sperm formation
34
What goes through more cells divisions sperm or eggs?
Sperm
35
When does gametogenesis commence in males?
Puberty
36
When does gametogenesis commence in females?
Early embryonic life
37
How many sperm are there per ejaculation?
100-200 million
38
Briefly describe the process of fertilisation
Two haploid cells form 1 diploid cell (zygote)
39
What does the zygote develop into?
Embryo
40
What is the name of the cell formed at fertilisation called?
Zygote
41
Where are mitochondria inherited from?
The maternal side
42
What is X inactivation in female mammals?
In the early embryo there can be a random inactivation of one of the X chromosomes
43
What are the 3 types of general chromosome abnormalities?
Numerical Structural Mutational
44
What is the incidence of chromosome abnormalities in miscarriages?
50%
45
What is the incidence of chromosome abnormalities in still born infants?
5%
46
What does trisomy mean?
Three copies of the chromosome
47
What is the disease caused by trisomy 21?
Down syndrome
48
What is the average life expectancy of someone with down syndrome?
50-60
49
Is trisomy 21 usually from the paternal or maternal origin?
Maternal
50
What disease does trisomy 13 cause?
Patau syndrome
51
Is trisomy 13 usually from the maternal or paternal origin?
Maternal
52
What does trisomy 18 cause?
Edwards syndrome
53
What is the prognosis of Edwards syndrome?
Most patients die within the first year and many die within the first month
54
Is trisomy 18 usually from the maternal or paternal origin?
Maternal
55
What is a balanced translocation?
This is when there is an even exchange of material between chromosomes with no genetic information extra or missing
56
What is an unbalanced translocation?
Where the exchange of chromosome material is unequal and results in extra or missing genes
57
How many chromosomes are there in robertsonian translocation/
45
58
What type of mutation is robertsonian?
Translocation
59
What happens in robertsonian translocation mutation?
Two chromosomes are fused together but no genetic information is lost
60
What is a deletion mutation?
A mutation where part of the genetic material is deleted and therefore missing
61
What is an inversion mutation?
When a piece of DNA is flipped end on end
62
What are the 2 types of inversion mutations?
Paracentric | Pericentric
63
What is a paracentric inversion mutation?
There is a break and the DNA is reinserted
64
What is a pericentric inversion mutation?
There is a break and the DNA is reinserted at the centromere position
65
What is polymorphism?
The natural variation that occurs in all people
66
Does polymorphism cause any disease?
No - it does not cause any disease whatsover
67
What is a silent mutation?
when the bases change but it codes for the same amino acid - therefore the mutaiton goes unoticed
68
What is a missense mutation?
When there is a change in one base and one amino acid. The protein makes come sense but not the original sense
69
What is a nonsense mutation?
There is a change in base, there is a change in one amino acid - however it becomes a stop codon - the protein synthesis makes no sense
70
What is a frameshift mutation caused by?
Deletion and insertion
71
What is the effect of frameshift?
All bases are subsequently changed
72
Is PCR and in vitro or in vivo technique?
In vitro
73
What are the three step of PCR?
Denature Anneal Extend
74
Roughly how many times is PCR repeated?
20-30 times
75
What is the purpose of PCR?
To amplify DNA
76
What does gel electrophoresis separate DNA fragments according to?
Size
77
What charge does DNA have?
Negative charge

Principles of Disease (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions