Which genes are most likely to travel
together?
a. genes on homologous chromosomes
b. genes on the same chromosome
c. genes separated by the smallest distance, in map units, on the
same chromosome
d. genes at the opposite tips of the
same chromosome
In a three-point cross, which group is the double
crossovers?
a. the largest proportion
b. the smallest proportion
c. there are no double crossovers in a three-point cross
d. the sum of the single crossovers
In a cross between a fly with the recessive traits a
and b and a fly heterozygous for these traits, all the
offspring are either wild type or exhibit both recessive traits.
This suggests that the loci for traits a and b
are:
a. unlinked.
b. more than 50 map units apart.
c. completely linked.
d. Linkage information cannot be inferred from this result.
In a testcross between a fly that is
a+b+c+ and heterozygous at all three
loci and a fly that is a b c, the smallest phenotypic
class is a+b c. What is the order of these genes
on the chromosome?
a. a b c
b. a c b
c. b a c
d. c b a