1. Chromosome 21:
a. is the shortest chromosome
b. is acrocentric
c. is in the A group of chromosomes
d. carries the gene for growth hormone.
e. trisomy causes Down's syndrome
2. The following are true about the Y chromosome:
a. the long arm is referred to as the p arm
b. the long arm has variable length
c. it demonstrates fluorescence with quinacrine
d. the short arm contains gene for testicular formation
e. fragile Y chromosome is associated with mental
3. In the DNA structure:
a. the backbone is made up of an alternate molecule
of pentose sugar and phosphate.
b. most coils are left-handed
c. there is a terminal hydroxyl group at one end
of the chain
d. there is a terminal phosphate group at only one
end of the chain.
e. if one chain has -AGG- the other chain has
the sequence -TCC-.
4. The following are true:
a. Turner's syndrome is usually due to non-dysjunction
in the spermatozoon
b. half the daughters of Turner's syndrome are
affected by the same condition
c. patients with XXY are infertile
d. all daughters are carriers in X-linked dominant disease
e. the recurrence rate for polygenetic conditions is 1-5%
5. The following are true about cytoplasmic messenger RNA:
a. it is mainly translated from nuclear DNA
b. has a larger molecular weight than heterogeneous
c. contains uracil in place of thymine
d. the sugar moeity is deoxyribose.
e. is manufactured when the embryo is at the one