Genes

Question 1

What is the definition of genomics?

Answer 1

Characterized by the study of all genes found in an organism

Question 2

What is the name given to genes that are expressed?

Answer 2

Exon (expressed)

Question 3

A what stage are introns spliced out of pre-mRNA?

Answer 3

Just before translation.

Question 4

What is the average size of a human exon?

Answer 4

145 kilobases

Question 5

What is seen as downstream in the context of DNA coding?

Answer 5

This is seen as the direction from the 5’ towards the 3’ end.

Question 6

What does the ‘One-gene one-enzyme’ rule refer to?

Answer 6

The idea that a portion of a DNA molecule produces one enzyme

Question 7

The central dogma refers to…

Answer 7

information that can only be passed on through one way.

Question 8

What type of enzyme is used to generate complementary DNA strands from RNA?

Answer 8

Reverse transcriptase

Question 9

Exposure to air when urine is passed is typical of…

Answer 9

Alkaptonuria, genetic disease that tends to initiate the development of arthritis later on in life.

Question 10

Why is there a link betwen enzymes and genes with the example of Alkoptonuria?

Answer 10

People with Alkoptonuria pass homogentisic acid in their urine because they dont have the neccessary enzyme to metabolize it before the urine is formed. Genes control the synthesis of enzymes.

Question 11

What is a suitable experimental technique to analyse mutations?

Answer 11

Unmutated spores that can grow on minimal and complete mediums.

Question 12

Define auxotrophic

Answer 12

Needs ‘help’ to grow

Question 13

What is the purpose of mutated spores?

Answer 13

To apply changes to the genome of the spore to see what is needed to be fixed in order to survive minimal medium.

Question 14

How are mutated spores analysed to check for mutations?

Answer 14

• 20 amino acids that are needed living are added to minimal medium.
• Where the colony is synthezied shows which synthesis of proteins are being disrupted.

Question 15

Why are enzyme deficiencies so integral for identifying diseases?

Answer 15

Enzymes provide the machinery to carry out almost every single metabolic pathway that is needed to acheive proper function of cells to tissues to organs etc.

Question 16

Symptoms of SCA (sickle-cell anaemia)?

Answer 16

• Impair blood circulation
• Clog capillaries
• Leads to heart failure
• Pneumonia

Question 17

Electrophoresis is the technique used to gauge the length of DNA strands using an electrical field?

Answer 17

True

Question 18

Why do shorter strands of DNA travel further along a gel when under the influence of an electrical field?

Answer 18

DNA is negatively charged, attracted towards positively charged anode.

Shorter strands are smaller and so it is easier for them to get across the gel under its duress.

Question 19

What leads to the different folding found in sickle cell RBC’s?

Answer 19

Change in DNA sequence from glutamic acid to valine causes this change.