Chapter 7: Microbial genetics

Question 1

Define genome

Answer 1

All of the genetic information in a cell (or virus)

Question 2

Define chromosome

Answer 2

Structure composed of DNA that carries the hereditary information (genes)

Question 3

Define plasmid

Answer 3

Genetic information other than chromosomal DNA

Question 4

Define genotype

Answer 4

The inherent genetic make up of an organism

Question 5

Define phenotype

Answer 5

The expressed properties of an organism

Question 6

What are the components of a nucleotide?

Answer 6

1. Nitrogen base
2. Sugar
3. Phosphate group

Question 7

What is need to start the process of DNA replication?

Answer 7

1. Two strands of DNA,
2. DNA polymerase

Question 8

What do you end up with from DNA replication?

Answer 8

Two double-stranded DNA helices

Question 9

What is the role of DNA helicase?

Answer 9

To unravel the two strands of DNA helix

Question 10

What is the role of DNA gyrase?

Answer 10

Re-combines the new chromosome strands into the twisted helix

Question 11

Why is DNA replication termed “semi conservative”

Answer 11

New strand is half original half new template

Question 12

What is needed to start the process of transcription?

Answer 12

One strand of DNA, RNA polymerase

Question 13

What do you end up with in the process of transcription?

Answer 13

Single-stranded RNA

Question 14

What is the role of mRNA in the process of translation?

Answer 14

Carried the DNA message from chromosome to the ribosome

Question 15

What is the role of rRNA in the process of translation?

Answer 15

Combined with proteins to form the ribosomal subunits that provide the site for protein synthesis (translation)

Question 16

What is the role of tRNA in the process of translation?

Answer 16

Transfer the amino acids from the cytoplasm to the ribosome

Question 17

What is an intron?

Answer 17

A non-coding DNA

Question 18

What is an exon?

Answer 18

Express a protein

Question 19

What special enzyme caries out mRNA processing?

Answer 19

Ribozymes

Question 20

What is the location of a codon?

Answer 20

mRNA

Question 21

What is the location of the anticodon?

Answer 21

tRNA

Question 22

Define the process of translation?

Answer 22

Protein synthesis from RNA

Question 23

What is the start codon in translation?

Answer 23

AUG

Question 24

What does the start codon in translation code for in prokaryotes?

Answer 24

Formal-methionine

Question 25

What does the start codon in translation code for in eukaryotes?

Answer 25

Methionine

Question 26

What is a mutation?

Answer 26

Heritable change in the sequence of nucleotides in DNA that often make an organism unable to synthesize one or more proteins

Question 27

What are the causes of a mutation?

Answer 27

1. Mutagen 2. Errors during DNA replication

Question 28

What is a point mutation?

Answer 28

Substitution

Question 29

What is the effect of a point mutation on the genotype and phenotype?

Answer 29

Effects genotype but not phenotype

Question 30

What is a frame shift mutation?

Answer 30

Insertion or deletion

Question 31

What is the effect of frame shift?

Answer 31

Effects both genotype and phenotype

Question 32

What is a silent mutation?

Answer 32

No change in protein

Question 33

What is a missense mutation?

Answer 33

One amino acid is altered in the protein

Question 34

What is a nonsense mutation?

Answer 34

A stop codon is created and cease production of protein

Question 35

What is a mutagen?

Answer 35

Mutation-causing substance