ch 7

Question 1

point mutations

Answer 1

chemical changes in just one base pair of a gene

Question 1

what are the kinds of point mutations?

Answer 1

-subsitutions
-deletions and insertions

Question 2

what is a purine and pyrimidine?

Answer 2

purines: A and G
CUT A PIE (pierimadines) - C and T

Question 3

what are the two types of subsitutions?

Answer 3

Transition : purine to purine or pyrimidine to pyrimidine
Transversion purine to pyrimidine either conversion

Question 4

foward mutations? reverse mutations?

Answer 4

-wild type to a different allele to mutation
-mutant allele to wild type

Question 5

what was the fluctuation experiments two hypothesis?

Answer 5

-If a mutation arise as a direct response of seperate suspensions it will show equal numbers of mutations
-Mutations arise because the organism s directing the mutation because of environmental pressures (AFTER)
-If a mutation arises randomly, separate suspensions will show unequal numbers of mutations (BEFORE)

Question 6

genetic screen

Answer 6

let everything grow and look for mutants

Question 7

genetic selection

Answer 7

you only let mutants grow (Selective environment )

Question 8

when DNA pol makes mistakes how can it be fixed? issue ?

Answer 8

-3’-5’ exonuclease removes the mismatched nucleotides
- can lose its place and expand and contract the DNA

Question 9

Ames test

Answer 9

• Substances that mutate bacterial DNA are likely to mutate human DNA
  -checks for mutagens by comparing different substances to the control if the substance by itself is high (it is a mutagen) but if low then it is normal
  -when the mutagen is added with an enzyme that can tell you if the mutagen can become more toxic? if the number gets higher