Module 1

Question 1

Phenotype

Answer 1

the visible properties of a mutant

Question 2

Genotype

Answer 2

the specific allele composition of a cell

Question 3

Mutation

Answer 3

a heritable change to the sequence of DNA molecule

Question 4

Wild type

Answer 4

the initial “non-mutant” organism

Question 5

A mutant

Answer 5

an organisms carrying a mutation

Question 6

Forward mutation

Answer 6

a loss of function mutation that generates a mutant organism from a wild type one

Question 7

Reversion

Answer 7

a mutational event that converts a mutant organism back into a wild one

Question 8

Auxotroph

Answer 8

a micro-organism that can only grow in the presence off a specific growth supplements such as amino acids

Question 9

Point mutation

Answer 9

a mutation at a single point (often a single base pair)

Question 10

Substitution mutation

Answer 10

a mutation where one base pair in the DNA sequence is changed to another

Question 11

Frameshift

Answer 11

a base pair DNA is incorporated into, or are lost from, a gene

Question 12

Deletion Mutation

Answer 12

one or more base pair of DNA are lost from a gene

Question 13

insertion mutation

Answer 13

one or more base pairs of DNA are inserted into a gene

Question 14

Spontaneous mutation

Answer 14

a mutation that occurs in the absence of any mutagen or other external causes

Question 15

Lesion

Answer 15

In DNA, a chemical change (damage); this is not a mutation but can lead into mutation

Question 16

his+

Answer 16

does not require histidine for growth; denoted His+

Question 17

his or hisG

Answer 17

requires histidine for growth; denoted His-

Question 18

lac+

Answer 18

can use lactose as a source for energy; denoted Lac+

Question 19

lac or lacZ

Answer 19

cannot use lactose as a source of energy; denoted Lac-

Question 20

Bacteriophage

Answer 20

A virus that infects bacteria

Question 21

Fluctuation test

Answer 21

a test used in microbes to establish the random nature of mutation or to measure mutation rates

Question 22

Ames test

Answer 22

Test in which special stains of bacteria are used to evaluate the potential of chemicals to cause cancer

Question 23

Bacteriophage plaques

Answer 23

these are holes in lawn of bacteria where the bacteria have been killed by the phage

Question 24

Haploid

Answer 24

the presence of a single set of chromosome in an organism’s cell

Question 25

Complementation

Answer 25

production of a wild type phenoty

Question 26

wild type

Answer 26

genes that predominates in the natural population of organisms

Question 27

Indels

Answer 27

insertion of deletion of one or more nucleotides in a DNA base sequence

Question 28

complementation

Answer 28

production of wild type phenotype when two mutant haploid genomes bearing recessive mutations are present in the same cell

Question 29

Recombination

Answer 29

a process that results in new combinations of mutations (i.e. progeny is genetically different to parents)

Question 30

complementation

Answer 30

tells you if the mutation are in the same or different genes; progeny are genetically identical to parents

Question 31

Tautomerization of Bases

Answer 31

A base transiently flips into a different isomer that has different base pairing properties (a cause of mutations)

Question 32

DNA proofreading

Answer 32

• Reduces spontaneous mutations
• Works by DNA polymerase checking each newly synthesized base pair in a strand of DNA. If it has made a mistake it backs up, removes the incorrect base and then resumes the synthesis of DNA

Question 33

Mismatch Repair System

Answer 33

• detects mismatched base pairs in DNA molecules
• Distinguishes correct and incorrect strands of DNA