Nucleic Acids & Gene Expression

Question 1

What is a gene?

Answer 1

A region of DNA made up of nucleotides that serves as a template for creating an RNA molecule.

Question 2

What are the 2 classes of RNA?

Answer 2

Coding (mRNA) & non-coding

Question 3

What is non-coding RNA used for?

Answer 3

To assist expression of other genes, (might do this alongside ribosomes).

Question 4

Name an example where the central dogma ( DNA -> RNA -> Polypeptide) is not valid.

Answer 4

Eukaryotic cells contain non-viral chromosomal DNA, and members of mammalian LINE 1 repetitive DNA family can code for cellular reverse transcriptase which can produce DNA from RNA.

Question 5

How do ribose and deoxyribose differ on a chemical level?

Answer 5

Ribose sugar has a hydroxyl (OH) group attached to carbon no.2 instead of hydrogen (H)

Question 6

What is the structure of a purine?

Answer 6

2 interlocked rings of carbon and nitrogen atoms.

Question 7

What is the structure of a pyrimidine?

Answer 7

1 ring of carbon and nitrogen atoms.

Question 8

Which bases are purines and which are pyrimidines?

Answer 8

purines: A, G
pyrimidines: C, T, U

Question 9

What is a nucleoside?

Answer 9

base + sugar

Question 10

What is a nucleotide?

Answer 10

Nucleoside + phosphate

aka Phosphate + Base + Sugar