Immunopathology - Week 6 - Essential Genetics

Question 1

What does DNA stand for?

Answer 1

Deoxyribonucleic Acid

Question 2

What is the basic structure of DNA?

Answer 2

• Double helix shape
• There are 4 bases: Adenine, Thymine, Guanine and Cytosine.
• Adenine always joins with thymine, whereas guanine always joins with cytosine.
• If DNA is as a ladder, the bases form the steps, and the phosphate and sugar molecules form the vertical sides of the ladder.

Question 3

What is the Function of DNA?

Answer 3

• DNA contains the instructions for growth and development in humans and all livingthings.
• DNA is packaged into chromosomes th at contain all of our genes.

Question 4

What is the basic structure of RNA?

Answer 4

• A form of nucleic acid with generally 1
  strand only.
• The base thymine is replaced by uracil.

Question 5

What are the different types of RNA and their functions?

Answer 5

mRNA (Messenger RNA):
- It takes information from DNA in the nucleus to the
ribosomes.

tRNA (Transfer RNA):
- Main function is to transfer of amino acids during protein synthesis.

Ribosomal RNA:
* These are the major component of ribosomes
* The protein/RNA complexes responsible for
assembling proteins from the mRNA code
* It accounts for the majority of the RNA present in
the cell at any given time.

Question 6

What is the structure of chromosomes?

Answer 6

• Chromosomes are made up of DNA tightly coiled many times around proteins called histones that support its structure.
• Chromosomes have a constriction point called the centromere.
• The centromere divides the chromosome into two “arms”. The ‘“p” arm is the short arm of the chromosome and the “q” arm is the long arm of the chromosome.
• The location of the centromere on each
  chromosome gives the chromosome its characteristic shape, and can be used to help describe the location of specific genes.

Question 7

How many chromosomes are in every cell?

Answer 7

There are 46 (23 pairs) chromosomes in ever cell.
23 from the mother and 23 from the father.

Question 8

How many pairs of chromosomes are autosomes and how many are Sex Chromosomes?

Answer 8

22 pairs of Autosomes.
1 pair of Sex Chromosomes.

Question 9

Each chromosome contains many genes. The site where a specific gene is, is called?

Answer 9

The Locus.