Exam 2 deck 5

Question 1

Mutation

Answer 1

a change in the genetic material

-a stable, inherited change in the nucleotide sequence of DNA

Question 2

If a cell makes a mistake in DNA replication, but then fixes it, is that a mutation?

Answer 2

No. Mutations are permanent and passed down to daughter cells

Question 3

Do mutations affect the phenotype?

Answer 3

sometimes

Question 4

mutagen

Answer 4

an agent that causes induced mutations

Question 5

Spontaneous mutations

Answer 5

they happen in the absence of mutagens when DNA polymerase messes up

Question 6

Base substitution / Point mutation

Answer 6

incorrectly replacing one base with another

Question 7

Missense mutation

Answer 7

results in a different amino acid

Question 8

silent mutation

Answer 8

no change in amino acid

Question 9

nonsense mutation

Answer 9

results in a STOP codon

Question 10

Base deletions or insertions/ Frame shift mutation / indels

Answer 10

messes up entire reading frame

usually results in an amino acid sequence with no biological activity

Question 11

Mutagen creating a Base Analog

Answer 11

• chemical mutagen
• mutagen, like HNO2, oxidizes base, like A, and changes its chemical formula
• The messed up A now binds with C
• The messed up A is inheritable

Question 12

Ionizing Radiation

Answer 12

causes formation of ions that can oxidize nucleotides and break the deoxyribose-phosphate backbone

Question 13

UV radiation

Answer 13

creates Thymine dimers

Question 14

Photolyase

Answer 14

separates thymine dimers with energy from light

Question 15

Nucleotide Excision Repair

Answer 15

Enzyme snips out damaged DNA and DNA polymerase fills in the gap