Variation and Mutation

Question 1

\what is genetic variation ?

Answer 1

individuals having different phenotypes due to genetic differences from parent to offspring

Question 2

what is environmental variation?

Answer 2

individuals possessing different phenotypes as a result of exposure to different environments that have identical genotypes

Question 3

what is genotype by environment interactions ?

Answer 3

individuals with different phenotypes due to interaction of their genotypes with their environment

Question 4

what is phenotypic plasticity ?

Answer 4

an organism’s ability to show different traits (phenotypes) in response to a varying environment, acting as a crucial way to cope with changing conditions

Question 5

what is reaction norm?

Answer 5

the pattern or range of phenotypes that the same genotypes can have due to the environment ; environment interactions

Question 6

how does mutation and evolution tie together ?

Answer 6

without mutation there is no evolution

Question 7

what is mutation ?

Answer 7

it is a heritable change in genetic material (DNA) that allows for the change in allele frequencies on it own and is the source for genetic variation that allow natural selection and genetic drift to act on

Question 8

what is an evolutionary force/mechanism?

Answer 8

anything capable of changing population allele frequency on it own

Question 9

what is a point mutation ?

Answer 9

a single base pair change ex g to c

Question 10

what are the two type of point mutations which one is more common

Answer 10

Transition and transversion; transitional due to indels

Question 11

what is a transition point mutation ?

Answer 11

it is the substitution of a purine with a purine or a pyrimidine with a pyrimidine

Question 12

what is a transversion point mutation ?

Answer 12

substitution of purine with a pyrimidine vice versa

Question 13

what is a synonymous vs nonsynonymous point mutation ?

Answer 13

synonymous (silent) point mutation is when it doesnt change the amino acid and non synomous is when it changes the AA

Question 14

what is a nonsense mutation ?

Answer 14

a early stop codon

Question 15

what are indels

Answer 15

insertion and deletions of one or more nucleotides in a sequence which result in frame shifts

Question 16

what is pleiotropy ?

Answer 16

a single mutation that effects multiple phenotypic traits ex PKU

Question 17

what is PKU ?

Answer 17

it is phenylketonuria which is caused by a single mutation in an enzyme and build up phenylalanine in the body

Question 18

what are the 4 fitness effects of mutation ?

Answer 18

1. neutral mutation- no affect
2. Deleterious - reduces fitness
3. Beneficial mutations - increases fitness
4. Lethal- results in organism death

Question 19

what is codon bias ?

Answer 19

it is the non random use of synonymous codons for an AA

Question 20

what is paralogous ?

Answer 20

genes that are duplicated by unequally crossing over and they diverge in function

Question 21

what are orthologous ?

Answer 21

genes that share a common acesteral sequence and are seperated by speciation results in two daughter linneages

Question 22

what does non coding DNA do?

Answer 22

it can create new genes

Question 23

what is a genetic cline ?

Answer 23

an increase or decrease in frequency of an allele or genetic variant over geographic distant

Question 24

what are inversions ?

Answer 24

it is the ionizing radiation of large chromsomes that reverse the order and prevent recombination which can affect linkage and gene order

Question 25

what is poly ploidy ?

Answer 25

it is a large scale mutation that is a duplication of entire sets and occurs in self fertilization autopolyploids usually from errors in meiosis

Question 26

why is polyploidy important?

Answer 26

it can result in new species and gaining new function

Question 27

what is an example environmental variation

Answer 27

water fleas (daphnia) within predation habitats developing defenses compared to those not in predation

Question 28

what is an example of genotype by environment interaction

Answer 28

with leopard geckos, their sex (phenotype) is determined by the temperature of incubation even though they had the same genotype

Question 29

what is the difference between sickle cell homozygosity and heterozygosity ?

Answer 29

those who are homo have sickle cell anemia however those who are heterozygot are resistant to malaria

Question 30

what are the 2 types of gene duplication?

Answer 30

1. Duplication by Unequal crossing over 2. Duplication by retroposition- reversed transcribed

Question 31

what are 3 gene duplication result in?

Answer 31

loci that either keep their function, gain a new function or become non functional (pseudogene) and overall results in the evolution of gene families