mutations and dna repair

Question 0

spontaneous Mutation

Answer 0

random event, not cause

Question 1

two steps to a mutation occuring

Answer 1

1. damage to the DNA

2. DNA repair mechanisms fail to correct it before next cell division

Question 2

Induced Mutation

Answer 2

Chemical or Radiation Caused event

Question 3

Somatic Mutation

Answer 3

Mutation not inherited through reproduction

Question 4

Germ Line Mutation

Answer 4

Inherited through reproduction

Question 5

Morphological Mutations

Answer 5

Physically observable mutations

Question 6

Behavioral Mutations

Answer 6

Common in animals

Question 7

Regulatory mutation

Answer 7

Operon mutation based on how much is produced, not what is produced. (cancer)

Question 8

Nutritional or Biochemical mutation

Answer 8

Operon mutation based on what is being produced

Question 9

Lethal Mutations

Answer 9

organism does not survive to adulthood

Question 10

conditional or temperature sensitive mutations

Answer 10

only expressed under certain conditions

Question 11

Bacterial or fungi Mutation Detection

Answer 11

Growth one minimal medium ( minimal nutrients) vs. complete medium (Beadle and Tatum

Question 12

Attached- X procedure? Explain.

Answer 12

In drosphilia and other species, XX is female and X is male; Y is irrelevant. Two X’s may become attached, if an attached x and one x are inherited they will die. If two Y’s are inherited they will die. Attached x and y, or x and y will live. All males that survive have mutation, and all females are fine.

Question 13

Plant Mutation Detection

Answer 13

Visual; biochemical analysis; Can culture the cells of the plant to observe them.

Question 14

Human Mutation detections

Answer 14

Pedigree analysis; culturing of cells; electrophoresis/sequencing

Question 15

transitions

Answer 15

Purine to purine ( alters structure of helix) Easily detected and repaired

Question 16

Tranversion

Answer 16

Purine to pyramiding ( won’t change dimension of helix) less likely to be repaired

Question 17

Silent/ synonymous Mutation

Answer 17

Base/point mutations. Will not alter polypeptide sequence

Question 18

Missense/ Nonsynonomous Mutation

Answer 18

Base or point mutation. Will alter amino acids

Question 19

Nonsence mutation

Answer 19

Base/point mutation. Introduce a termination codon

Question 20

List types of Base substitution/ point mutations.

Answer 20

1. Transition
2. Transversion
3. silent/synonymous
4. Missense
5. non-sense

Question 21

Base Substitution

Answer 21

base added, alters a single codon

Question 22

base insertion or deletion

Answer 22

alters reading frame and may change many codons

Question 23

spontaneous Mutation Rates

Answer 23

Due to replication error, tautomeric shifts, apurination, or deamination; not induced by external agent

Question 24

Mutation rate? spontaneous

Answer 24

very low rate. Varies among species. varies among genes of same species.

Question 25

Tautomeric Shift

Answer 25

Protons shift from one atom to another. changes the position of hydrogen bonds that can form, will not pair as stably.

Question 26

what is the result of tautomeric shifts?

Answer 26

bases pair with bases that aren't their normal base pairs. A and C. T and G.

Question 27

Apurination

Answer 27

Spontaneous lesions, breaking of glycosidic linkage between deoxyribose and a purine. The AP site

Question 28

What is the result of Apurination?

Answer 28

stalled replication, or base substitution

Question 29

Deamination?

Answer 29

Loss of amino group from base structure.

Question 30

Where does Deamination occur?

Answer 30

A or C | Amino to keto shift

Question 31

What does C form when deaminated?

Answer 31

urycil

Question 32

What does A form when Deaminated?

Answer 32

hypoxanthine pairs with C

Question 33

Base analogs

Answer 33

Substitute for normal nucleotides (induced mutation)

Question 34

Alkylating Agents

Answer 34

Alkylates bases, causing transition (changes how things pair)

Question 35

Acridine Dyes

Answer 35

intercalating agents, resulting in frameshift mutations

Question 36

UV Radiation

Answer 36

formation of pyrimidine dimers, Inhibits replication

Question 37

Ionizing radiation- Xrays- gamma rays- cosmic rays

Answer 37

causes chromosome breakage, causes point mutations

Question 76

The Ames test

Answer 76

Tests to see if there is chemical mutagenicity

Question 77

Photoreactivation Repair

Answer 77

DNA repair in prokaryotes | requires exposure to blue light photoreactivation enzyme (PRE) cleave thymine dimer

Question 78

Excision repair

Answer 78

Prokaryia or eukaryianuclease detects and remores incorrect base; polymerase 1(prokaryia) inserts correct nucleotide, ligase seals the gap

Question 79

2 types of Excision repair

Answer 79

Base ER | Nucleotide ER

Question 80

proofreading

Answer 80

DNA repair mechanism, Polymerase I proofreads shortly after replication

Question 81

Mismatch repair

Answer 81

Recognition of methylated template strand | repair enzymes MutH, MutL, MutS, MutU

Question 82

Post-replication Repair

Answer 82

if a lesion is skipped at replication, it is repaired by recombination with the undamaged complementary strand

Question 83

SOS repair

Answer 83

Several mutations detected, many proteins involved, allows DNA polymerase to replicate across lesions

Question 84

double strand break repair

Answer 84

Mammals. break in both strands

Question 85

homologous recombinational repair

Answer 85

mammals- crossing over homologous chromosomes, break in two strands.

Question 86

site directed mutagenesis

Answer 86

Introducing specific mutations

Question 87

site directed mutagenesis steps

Answer 87

1. determine gene sequence 2. isolate one strand 3. add synthetic oligonucleotide 4. strand hybridize 5. semiconservative replication occurs result- mutant protein