Mutations and DNA Extraction

Question 1

Spontaneous Mutations

Answer 1

Mutations that are the result of errors in DNA replication (occurs without chemical change or radiation)

Question 2

Induced Mutations

Answer 2

Mutations caused by chemical or physical agents (mutagenic agents)
- Chemical agents have structure similar to nucleotides, interact with DNA chemically (ex. cigarettes, nitrate)
- Physical agents tear through DNA’s structure (ex. UV, X-ray)

Question 3

Single Gene Mutations

Answer 3

Changes in the nucleotide sequence of one gene

Question 4

Point Mutations

Answer 4

One nucleotide is altered, removed, or inserted

Question 5

Substitution

Answer 5

One nucleotide is replaced with another nucleotide

Question 6

Substitution: Silent

Answer 6

No change in amino acid

Question 7

Substitution: Nonsense

Answer 7

Results in a STOP codon

Question 8

Substitution: Missense

Answer 8

Change in amino acid:
Conservative: no change in type of amino acid - protein may fold the same
Non-Conservative: change in type of amino acid - folds differently

Question 9

Frameshift

Answer 9

A nucleotide is inserted or removed, changing the reading frame

Question 10

Chromosomal Mutation

Answer 10

Involves changes in many genes

Question 11

Chromosomal: Translocation

Answer 11

One section of one chromosome swapped with another section of a different chromosome

Question 12

Chromosomal: Inversion

Answer 12

A piece of the chromosome turns around then re-inserts itself

Question 13

Chromosomal: Other

Answer 13

Deletion, insertion, duplication

Question 14

DNA Extraction

Answer 14

1. Squish - separates cells
2. Add salt solution - dissociates: NaCl –> Na+ + Cl- where positive Na+ ion binds to negatively charged phosphate groups on DNA to stabilize it and prevent it from tangling
3. Add soap - denatures proteins & lipids, breaking down nuclear membrane
4. Filter - remove large pieces and further separate cells
5. Add ethanol - precipitates DNA