Biology
Biomolecules Solutions
8. On a chromosome, genes A and Ware 5 map
units apart, W and G are 15 units apart, E and
Gare 12 units apart, and W and E are 3 units
apart. Between which two genes would you
expect the highest recombination frequency?
(A) A and w
(B) Wand G
(C) E and G
(D) Wand E
(E) A and G
10. Calmodulin is an intracellular signaling
molecule that complexes with calcium ions in
order to activate certain protein kinases.
These protein kinases can be activated by the
direct binding of Ca2+ 1 calmodulin
complexes or by autophosphorylation of the
kinase subunit. In the unphosphorylated
state, one would expect the kinase subunit to
(A) be constitutively active.
(B) phosphorylate target proteins that are
nearby
(C) be inactive.
(D) be unable to bind calmodulin.
(E) act as a transducer of calcium signals.
9. The structure pictured above shows the
arrangement of microtubules that can be
found within
(A) cilia.
(B) flagella.
{C) basal bodies.
(D) sarcomeres.
(E) motor kinesins.
11. The sex-determination pathway in Drosophila
results in the formation of either a male or
female because of the presence or absence of
key proteins coded for by a single gene known
as double-sex. The double-sex gene codes for
the protein dsx' in order to build a female
fruit fly, but it codes for the related protein
dsx" in order to build a male fruit fly. It is
therefore appropriate to conclude that
(A) the two protein products of the double-
sex gene are created by alternative RNA
splicing in male and female fruit flies.
(B) the protein products differ in males and
females because females have two copies
of the double-sex gene and males only
have one.
(C) RNA polymerase in females reads the
double-sex gene differently than it does
in males, altering the transcription of the
sex-determining gene.
(D) the dax' and dsx™ proteins must have
different signal sequences, allowing them
to go through alternative post-
translational modifications
(E) the proteins coded for by the double-sex
gene have little to do with the presence of
or Y chromosomes in the cells of Drosophila
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