Genetics

Question 1

Operon

Answer 1

set of genes that are cotranscribed

Question 2

Polysystronic mRNA

Answer 2

will be translated into several proteins

Question 3

Genome:

Answer 3

entire complement of all genes in cell or virus

Question 4

Chromosome:

Answer 4

main genetic element in 
Other genetic elements:
virus genomes
plasmids
organellar genomes
transposable elements

Question 5

Plasmid

Answer 5

is a genetic element that is expendable and rarely contains genes for growth under all conditions

Question 6

R plasmids

Answer 6

Resistance plasmids; confer resistance to antibiotics and other growth inhibitors
Widespread and well-studied group of plasmids
Many are conjugative

Question 7

In what direction does replication occur?

Answer 7

5’ to 3’

Question 8

Replisome

Answer 8

complex of multiple proteins involved in replication

DNA pulled through the replisome

Question 9

Leading strand

Answer 9

has continuous synthesis

Question 10

Lagging strand

Answer 10

has discontinuous synthesis

Question 11

Okazaki fragment

Answer 11

short DNA fragments on lagging strand

Question 12

DNA polymerase I

Answer 12

replaces RNA primer with DNA sequence

Question 13

DNA ligase

Answer 13

covalently joins successive Okazaki fragments together

Question 14

Codon:

Answer 14

a triplet of nucleic acid bases encodes a single amino acid

Question 15

Chaperonins

Answer 15

They only assist in the folding, are not incorporated into protein
Can also aid in refolding partially denatured proteins
Extreme temperatures and pH