mutation mod31

Question 1

the 2 types of mutation

Answer 1

changes in chromosome number and point mutation

Question 2

what is a mutant

Answer 2

someone who exhibits a special phenotype

Question 3

recombination mechanisms do what

Answer 3

rearrange genetic variability into new combinations

Question 4

natural selection preserves what

Answer 4

the combinations best adapted to existing environment

Question 5

Germinal mutations occur

1) in what cells
2) how do they affect progeny

Answer 5

1) germ line cells

2) transmitted though the gametes to the progeny

Question 6

Somatic mutations occur

1) in what cells and phenotype will only occur in what
2) affect progeny how

Answer 6

1) somatic cells, mutant phenotype will occur only in the descendants of that cell
2) not be transmitted to the progeny

Question 7

Spontaneous summations occur and are frequent or infrequent

Answer 7

occur without a known cause due to inherent metabolic errors or unknown agents in the environment
Infrequent

Question 8

Induced mutations result from

Answer 8

from exposure or organisms to mutagens, physical and chemical agents that cause changes in DNA, such as ionizing irradiation, ultraviolet light, or certain chemicals

Question 9

Is mutation random

Answer 9

yes

Question 10

is muation non adaptive

Answer 10

yes

Question 11

does environmental stress cause mutations

Answer 11

No, selects mutants best adapted to environmental stress

Question 12

when does mutagenesis occur inbacteria

Answer 12

when populations of bacteria stop growing (in stationary growth phrase)

Question 13

increase in mutagenesis is due to induction of what

Answer 13

error prone dna repair processes

Question 14

adapted mutation is NOT equal to what

Answer 14

direct mutation

Question 15

Forward muation is

Answer 15

wild type allele to a mutant allele

Question 16

reverse mutation is what

Answer 16

second mutation that restores the original phenotype

Question 17

Back mutation is what

Answer 17

second mutation at the same siite

Question 18

Suppresor mutatoin is what

Answer 18

second mutation at a different location in the genome

Question 19

The progeny will have what phenotype if its a back mutation

Answer 19

All progeny will have the wild type phenotype

Question 20

The progeny will have what progeny if its a supressor mutation

Answer 20

some of the progeny will have the mutant phenotype

Question 21

How to distinguish between supressor and back mutation

Answer 21

backcross the phenotypic revertant with the wild-type

Question 22

In diploids, most recessive mutations will not be what but what is an exception

Answer 22

not be recognised but X linked recessive mutations are an exception

Question 23

What are neutral mutations

Answer 23

when the mutations have no effect on the phenotype

Question 24

X linked recessive lethal mutations alter what ratio

Answer 24

sex ratio because the mutation will cause one progeny to die

Question 25

Recessive mutations often block what

Answer 25

metabolic pathways

Question 26

How can recessive mutations affect metabolic pathway

Answer 26

Enzymes are encoded by genes, alterations of these genes then means the enzyme is changed which affects metabolic pathways

Question 27

Hemoglobin mutation leads to sickle cell anemia, what is the mutation

Answer 27

6th amino acid in hemoglobin S is valine when it should be glutamic acid.
Mutation is of single bae pair

Question 28

Tay sachs is what type of disease and what is the mutation

Answer 28

autosomal recessive disease, gene encoding hexosaminidase A

Question 29

Conditional lethal mutations are what (2 things)

Answer 29

lethal in restrictive conditions but viable in the permissive coondition

Question 30

mutants with conditional lethal alleles can be propagated under what conditions and the phenotype can be studied under what conditions

Answer 30

proagated under the permissive condition and studied under restrictive conditions

Question 31

what are the 3 major types of lethal conditions

Answer 31

auxotrophs, temp sensitive and suppressor sensitive

Question 32

how are conditional lethal mutations used to study biological pathways

Answer 32

intermediate is allowed to form and then the mutation will prevent the prevent from being made and so the process can be seen