Questions -
Q1. You make a cross between two completely homozygous lines (line A and line B)
Assume A and B differ at 6 loci that segregate independently.
Assume each F1 plant produces 10,000 F2 seed.
How many F1 seed will you need for A x B in order to have a large enough F2 population to represent the cross?
a) 36 seed
b) 1 seed
c) 128 seed
d) 2 seed
e) 6 seed
Q2. You make a cross between two completely homozygous lines (line C and line D).
Assume A and B differ at 7 unlinked loci.
Assume that an F1 plant produces 150 seed.
How many F1 seed will you need for C x D to produce a large enough F2 population to represent all the possible genotypes?
a) 50 seed
b) 14 seed
c) 110 seed
d) 1 seed
e) 196 seed
Q3. You make a cross between A x B. Again, assume A and B differ by genes at 6 unlinked loci.
You make a top cross with another completely homozygous line C to construct the three-way cross A/ B//C.
Assume C does not increase the number of segregating loci and that each three-way cross F1 plant produces an infinite amount of F2 seed. Hence the of size of the F2 population is not a concern.
How many F1 seed will you need for A/B//C?
a) 1 seed
b) 2 seed
c) 6 seed
d) 64 seed
e) 128 seed
Q4. You make a cross between A x B.
Again assume A and B differ by genes at 6 loci.
You make a top cross with another completely homozygous line C (Final cross is A/B//C).
Again assume C does not increase the number of segregating loci.
This time, assume each top-cross F1 plant produces 250 F2 seed.
How many F1 seed will you need for A/B//C to completely represent the population?
Consider F2 population size in your calculation.
a) 64 seed
b) 16 seed
c) 47 seed
d) 128 seed
e) 256 seed
Q5. You make a cross between C x D, with another completely homozygous line F (Final cross is (C/D//F).
Again, assume C and D differ by genes at 7 unlinked loci.
Assume F increases the number of segregating loci by 2 new unlinked loci (C and D were homozygous and similar at these two loci).
Assume that each F1 plant produces 250 F2 seed.
How many F1 seed will you need for C/D//F? Consider the F2 population size.
a) 164 seed
b) 1049 seed
c) 128 seed
d) 262144 seed
e) 512 seed