Exam 2 - Lecture 4 (mutations) Key Terms

Question 1

Nucleotide-level Mutation

Answer 1

Specific changes caused int he DNA and phenotypic effects in proteins
- changing DNA bases

Question 2

Chromosomal-level Mutation

Answer 2

Occur when DNA molecules break and are rejoined incorrectly.
- caused by damaged chromosomes by mutagens(induced) or errors in chromosome replication (spontaneous)

Question 3

Induced Mutation

Answer 3

Are due to outside agents, or mutagens like chemicals, radiation, and retrovirus

Question 4

Spontaneous Mutation

Answer 4

Occur without outside influence and are permanent

Question 5

Heritable

Answer 5

Mutations can either be:
1. Passed onto daughter cells via mitosis (somatic cells)
2. Passed on to offspring via sexual reproduction (germ-line)

Question 6

Somatic

Answer 6

Occur in somatic (body) cells
- Passed onto daughter cells via mitosis but not to sexually produced offspring

Question 7

Germ-line

Answer 7

Occur in cells that give rise to gametes
- A gamete passes these mutations on at fertilization
- not all mutations are heritable this way

Question 8

insertion

Answer 8

Sequence level: can cause a frame-shift

Question 9

deletion

Answer 9

sequence level: can cause frame-shift
chromosomal level: chromosome breaks in two places and rejoins, leaving out part of the DNA

Question 10

substitution

Answer 10

sequence level mutation
- transition or transversions
- They are both equally likely to occur

Question 11

transition

Answer 11

(part of point mutation at the sequence level)
A type of substitution
- substitution of a purine for a purine or a pyrimidine for a pyrimidine

Question 12

transversion

Answer 12

(part of point mutation at the sequence level)
A type of substitution
- Substitution of a purine for a pyrimidine or vice versa

Question 13

frame shift

Answer 13

A sequence-level mutation due to insertions/deletions
- when bases that aren’t a multiple of three are deleted or inserted and the reading frame shifts

Question 14

duplication

Answer 14

Chromosomal level mutation
- When homologous chromosomes break at different places and rejoin incorrectly

Question 15

inversion

Answer 15

Chromosomal level mutation
- Chromosome breaks and reattaches in reverse orientation

Question 16

translocation

Answer 16

Chromosomal level mutation
- A segment of a DNA breaks off and attaches to a nonhomologous chromosome
- can lead to deletions and duplications

Question 17

tautomer

Answer 17

A molecule with the same chemical formula but a slightly different structure