Mutation and repair

Question 1

Mutation

Answer 1

Any heritable trait in genetic material.

Causes variation in genomes.

Question 2

Somantic mutations

Answer 2

Mutation is not transmitted to offspring.
(green chain with one blue, blue chain builds off of blue and has one red, red chain builds off of red and has one orange…)

Question 3

Point mutations

Answer 3

Small-scale mutations that are generally synonymous (silent) - no change in amino acid.
Can also be non synonymous or cause nonsense mutations (when a codon changes to a stop codon)
Ex) T-A is replaced with C-G

Question 4

Frameshift mutations

Answer 4

Large-scale mutation.
Is the addition or deletion of a base.
Ex) THE BIG BOY SAW THE CAT EAT THE BUG
*remove the E in THE and the result is unintelligible*
THB IGB OYS AWT HEC ATE ATT HEB UG

Question 5

Transpons

Answer 5

DNA sequences that can move from one position to another in the genome.
Duplication: sequence is doubled.
Deletion: sequence is gone.
Ex) maize with different colored pigments.

Question 6

What causes mutations?

Answer 6

UV light, X-rays, chemicals

Question 7

Base excision repair

Answer 7

Cut out a single base and replace.
Abnormal or damaged bases can be removed from the backbone.
Repair polymerase inserts the correct nucleotide into the gap.

Question 8

Nucleotide excision repair

Answer 8

Repairs a sequence of DNA containing mismatched or damaged bases at once.

Question 9

Mismatch repair

Answer 9

After replication, if DNA polymerase doesn’t catch a mistake with the parental strand and newly synthesized strand.

1) Marks incorrect base area with a cut.
2) An exonuclease removes the incorrect nucleotide.
3) DNA polymerase inserts the correct nucleotide.
4) DNA ligase joins the nucleotide to the nucleotides on its sides and to the complementary strand.