ANSWER ALL the PARTS you can
PART1 Alleles are considered linked if recombination is less than 50% in:
a) a Px P Fl cross
b) an F1 x F1F2 cross
c) an F2 x F2F3 cross
d) an Fl x homozygous recessive cross
e) any F2 progeny x homozygous recessive cross 1.
PART2 If two loci A/a B/b are 9 map units apart, and an Ab/aB individual is testcrossed,
a) There will be 9% AB individuals
b)There will be 91% Ab individuals
c) There will be 4.5% ab individuals
d) There will be 91% recombination individuals
If two genes a and b show 50% recombination genes a and c show 35% recombination, and genes b and show 32% recombination, then
a) Genes a and b are on the same chromosome, and 50 m.u. apart
b) Genes a and b are on different chromosomes
c)Genes a and b are on the same chromosome, and 67 map units apart
d) One cannot tell if genes a and b are on the same or different chromosomes from given data.
PART4 If two genes a and b are 8.3 m.u. a part, one expects to find
a) 8.3% recombinant gametes from a double heterozygous parent
b) 91.7% recombinant gametes from a double heterozygous parent
c) A chiasma between the a and b loci in 8.3% of the meiosis
d) A chiasma between the a and b loci in 91.7% of the meiosis.
PART5 Map distances are most accurate when genes are closely linked because as genes become further apart,
a) They always show independent assortment
b)The chance of multiple crossovers increases
c) They no longer recombine
d) There is chiasma interference
PART6 In a three-point testcross, the most frequent classes of progeny were ABc and abC. The less frequent classes of progeny were AbC and aBc. Which gene is in the middle?
a) Aa
b) B/b
c)C/c
d) It is not possible to tell from just these data
PART7 In a three-point testcross with 100 progeny, there were 16 single crossovers between genes A and B, 29 single crossovers between genes B and C, and 4 double crossovers. The correct gene order was determined to be A-B-C. What is the map distance between A and B?
a) 20%
b) 0.2 m.u
c) 20 m.u.
d) 16 m.u.
e) 29 m.u.
f) 16%
