chapter 15

Question 1

A single nucleotide base in the DNA sequence is altered.

Answer 1

Point Mutation

Question 2

Base insertions/deletions

Answer 2

indel mutations

Question 3

replacing a base pair with another “wrong base”

Answer 3

base substitution

Question 4

replacement of a base by another base in the same category (purine for purine)

Answer 4

transition

Question 5

replacement of a base by another in a different category (purine for pyrimidine)

Answer 5

transversion

Question 6

replaces a codon with another codon that produces the same amino acid (silent mutation)

Answer 6

synonymous mutation

Question 7

replaces a codon with another codon that produces a different amino acid (missense mutation)

Answer 7

nonsynonymous mutation

Question 8

codon is changed to a stop codon

Answer 8

nonsense mutation

Question 9

what is a conservative nonsynonymous mutation

Answer 9

same amino acid type (polar on polar)

Question 10

what is a nonconservative nonsynonymous mutation

Answer 10

different amino acid type (base instead of acidic)

Question 11

addition/removal of a base in a coding sequence altering the codon “reading frame” downstream of the indel mutation

Answer 11

frameshift mutation

Question 12

what are the two causes of mutations?

Answer 12

Spontaneously produced by the cell AND induced by things called mutagens

Question 13

bases that can appear in more forms that differ the position of atoms and differ bonds

Answer 13

tautomers

Question 14

Are naturally occurring damage to DNA resulting from depurination and deamination

Answer 14

spontaneous mutations

Question 15

highly reactive molecules that are produced during normal metabolic processes in living organisms

Answer 15

oxygen radicals

Question 16

mutations elicited by environmental agents which are mutagens

Answer 16

induced mutations

Question 17

What are examples of induced mutations?

Answer 17

UV light, Ionizing raiation, base analogs (causes incorrect base to be incorporated)

Question 18

what is MGMT

Answer 18

methyltransferase enzyme that demethylizes bases

Question 19

Using the undamaged strand as a template of reference to repair damaged strand

Answer 19

single stranded damage repair

Question 20

repairs a single nitrogenous base using an enzyme, Glysodase

Answer 20

base excision

Question 21

repairs helix damage and is most evolutionarily conserved (removes surrounding unaffected bases as a precautionary)

Answer 21

Nucleotide excision repair

Question 22

When does mismatch repair take place?

Answer 22

Post replication

Question 23

What type of double stranded break is error prone, ~30 minutes, and has sticky ends

Answer 23

Nonhomologous end joining

Question 24

What type of double stranded break is error prone, ~7 hours and is similar mechanism to crossing over during meiosis.

Answer 24

Homologous recombination

Question 25

a cellular process that allows cells to bypass DNA lesions (damage) during DNA replication

Answer 25

Translesion synthesis

Question 26

Three charactersitics of cancer

Answer 26

1. Rapidly grow 2. Decrease cell's suseptability to die 3. Increases mutation rate

Question 27

Genes that when mutated act dominantly to contribute to tumor formation

Answer 27

Onco-genes

Question 28

genes that when mutated, act recessively, resulting in the loss of a genes normal function

Answer 28

tumor suppressor genes