Genetics

Question 1

2 factors of disease

Answer 1

Environment + genetics

Question 2

What direction is DNA read in?

Answer 2

5’ to 3’ direction

Question 3

Structure of DNA?

Answer 3

Strands of DNA pair up in anti-parallel fashion
Sugar-phosphate Backbone
The information is held in the base sequence, which is along a sugar-phosphate backbone

Question 4

Structure of a chromosome?

Answer 4

DNA strand associates with proteins (eg histones) and is wound into chromosome structure

Question 5

How can DNA be damaged?

Answer 5

Replication

- repair mechanisms exist however if they are defected that’s when disease occurs

Question 6

Meiosis; simple explanation?

Answer 6

One diploid parent cell becomes 4 haploid daughter cells.
Gamete formation
Crossing over occurs

Question 7

DNA bases?

Answer 7

Adenine
Thymine
Cytosine
Guanine

Question 8

Summary of Cell Cycle?

Answer 8

G1 (Gap 1)  
(G0 is in between these) rest phase
S (where DNA synthesis occurs)
G2 (Gap 2)
M (Mitosis)
G1

Question 9

When does DNA replication occur?

Answer 9

S phase

Question 10

Mitosis

Answer 10

1 diploid parent cell

2 Identical diploid daughter cells

Question 11

Structure of RNA

Answer 11

Single Stranded
Ribose sugar backbone
Uracil replaces thymine

Question 12

Transcription/Translation

Answer 12

DNA transcribed to pre- mMRNA
Pre mRNA pliced (introns removed) = mRNA
mRNA translated to a protein
Protein is modified and moved around the cell

Question 13

3 bases code for

Answer 13

Amino acid
Or
Stop Codon

Question 14

The amount of protein produced depends on?

Answer 14

Rate of transcription
Rate of splicing to mRNA
Half life of mRNA
Rate of of processing of polypeptide

Question 15

Sequence variations within a gene?

Answer 15

Change to promoter sequence

Change to exon sequence

Question 16

Sequence Changes in the DNA between genes?

Answer 16

SNPs (Single nucleotide polymorphisms)

Larger deletions or duplications

Question 17

Polymorphism Definition?

Answer 17

Any variation in human genome with a frequency of more than 1%
Does not cause disease in own right however may predispose to a common disease

Question 18

Mutation

Answer 18

Any heritable disease in the human genome

Gene change that causes a genetic disorder

Question 19

Multifactorial Disease?

Answer 19

Multiple polymorphisms cause a risk of disease