Topic 4

Question 1

most consequential deviation of mendels law

Answer 1

genetic linkage

Question 2

recombination frequency reflects

Answer 2

distance between genes

Question 3

where does crossing over happen

Answer 3

F1 / meiosis 1
(prophase of the first division and after S phase)

Question 4

is crossing over less effective than assortment for generating recombination

Answer 4

yes

Question 5

does crossing over happen more close or far

Answer 5

far

Question 6

does mendels second law apply to linked genes

Answer 6

no

Question 7

law of segregation

Answer 7

first law - ensures every gamete gets one allele

Question 8

law of independent assortment

Answer 8

second law - each trait segregates independently of each other

Question 9

when genes are linked, do you see more parental phenotypes

Answer 9

yes

Question 10

recombinants between linked genes appear due to

Answer 10

crossing over

Question 11

if CO did not happen at all in gene linkage , what would the outcome be

Answer 11

100% parental

Question 12

3 characteristics of CO

Answer 12

happens in meiosis 1
happens after DNA replication
impacts 2/4 chromosomes

Question 13

recombination between tightly linked genes is always less than ____%

Answer 13

50

Question 14

what number of crossovers are detectable

Answer 14

odd numbers

Question 15

coupling

Answer 15

cis (same side / same gene)
“likes with likes (AB/ab)”

Question 16

repulsion

Answer 16

trans (opposite genes)
“mixed pairs (heterozygote)”

Question 17

A/a ; B/b means what

Answer 17

unlinked - separate chromosomes or far apart

Question 18

AB/ab means what

Answer 18

linked

Question 19

frequency of recombination measures

Answer 19

intensity of linkage

Question 20

RF close to 0 means

Answer 20

genes are very tightly linked

Question 21

who realized linkage was important to where they are on chromosomes

Answer 21

sturtevant

Question 22

RF will increase as distanced between genes __________

Answer 22

increases

Question 23

RF = 50 means what

Answer 23

CO will be happening in every meiocyte for the loci involved

Question 24

1% of recombination means what

Answer 24

1 unit of genetic distance

Question 25

maximal distance calculable from a cross

Answer 25

50 cM or RF 0.5

Question 26

genetic linkage (same chromosome) is measured in what

Answer 26

cM

Question 27

physical linkage is measured in what

Answer 27

bps

Question 28

syntenic

Answer 28

genetically linked on the same chromosome

Question 29

can you be syntenic and unlinked

Answer 29

yes if genes are very far apart. over RF 0.5

Question 30

RF equation

Answer 30

number of recombinant gametes / P + R gametes x 100

Question 31

rejecting the hypothesis is a case for what regarding gene linkage or not

Answer 31

linkage

Question 32

the shorter the map distance, the ______ likely it is to have double crossing over

Answer 32

less

Question 33

the gene that switches between the double recombinant and the parental genotypes is the

Answer 33

middle gene

Question 34

in a RF calculation, you should consider double recombinant how many times

Answer 34

twice

Question 35

are crossovers independent events

Answer 35

no

Question 36

the effect of a CO in preventing the appearance of another is referred as

Answer 36

interference

Question 37

I (interference) of close to 1 means what

Answer 37

that all the recombinants that we were supposed to see did happen

Question 38

is RF less reliable as distances get further

Answer 38

yes

Question 39

after what number do RF values underestimate recombination

Answer 39

7