Module 4: Nucleic Acids

Question 1

Plasmids

Answer 1

Carries only one or two genes

can replicate independently of core genome and be transferred from one cell to another (rapid spread of genes)

Question 2

Super coiling

Answer 2

Coiling that occurs in addition to coil helical DNA structure
preserves double helix and compact DNA into small space

Question 3

Streptococcal bacteria

Answer 3

Normal inhabitants of human upper respiratory tract
Benign strains harmless
Virulent strains -mild symptoms (sore throat) to severe (pneumonia)

Question 4

Transformation

Answer 4

Change in cell behaviour resulting from incorporation of hereditary material from outside cell

Question 5

Nucleotide

Answer 5

Phosphate group, five carbon deoxyribose sugar, nitrogenous base

Question 6

Pyrimidines

Answer 6

Cytosine and thymine

Single ring

Question 7

Purines

Answer 7

Guanine and adenine

2 rings

Question 8

Chargaff’s rules

Answer 8

A and T -2 hydrogen bonds

G and C -3 hydrogen bonds

Question 9

Messenger RNA/mRNA

Answer 9

Single stranded RNA molecules that is copy of gene that codes for protein
Translated by ribosomes

Question 10

Transfer RNA/tRNA

Answer 10

Carry amino acids into ribosomes and match amino acids to appropriate mRNA sequence
Not translated

Question 11

Ribosomal RNA/rRNA

Answer 11

Multiple rRNAs and proteins form functional ribosomes complexes that perform translation of mRNAs into proteins