AP BIOLOGY
Test Booklet
Week 5, Classwork, Unit 2
1.
Figure 1. Simplified diagram of cellular structures of Plasmodium falciparum
The eukaryotic protozoan parasite P. falciparum is the causative agent of malaria. P. falciparum cells contain an
organelle called the apicoplast (see Figure 1). Apicoplasts synthesize precursors of biomolecules that are required
for growth and reproduction of the parasite.
(a) Based on Figure 1, describe TWO pieces of evidence a researcher could use to support the claim that
apicoplasts evolved from free-living, prokaryotic organisms.
(b) Doxycycline is a drug used to treat malaria and some bacterial infections. Doxycycline binds to the prokaryotic
30S ribosomal subunit and inhibits its function. Explain how doxycycline can be an effective treatment for a P.
falciparum infection in humans.
AP Biology
Page 1 of 3
Test Booklet
Week 5, Classwork, Unit 2
2.
Read each question carefully. Write your response in the space provided for each part of each question.
Answers must be written out in paragraph form. Outlines, bulleted lists, or diagrams alone are not
acceptable and will not be scored.
Increased expression and activity of the ligand-gated ion channel
has been shown to block cell division
protein consists of several transmembrane
and induce apoptosis in human cells. The structure of the
domains that are embedded in the membrane as well as a carboxy-terminus and an amino-terminus that are located
inside the cell (Figure 1).
Figure 1. Structure of the
protein channel in the membrane
is activated by several stimuli, including the binding of capsaicin, a chemical found in chili peppers.
Capsaicin enters the cell by simple diffusion and then binds to one of the transmembrane domains of
,
which opens the ion channel.
channel allows
ions to enter the cell, leading to the activation of the enzyme
The opening of the
calcineurin. Calcineurin removes phosphate groups from the phosphorylated form of the transcription factor
, which is typically found in the cytoplasm. Once dephosphorylated,
moves into the nucleus,
.
, when active, prevents the cell cycle
where it blocks the transcription of another protein,
regulatory protein
from inducing apoptosis and blocking cell division (Figure 2).
Page 2 of 3
AP Biology
Test Booklet
Week 5, Classwork, Unit 2
Figure 2. Capsaicin-activated
signaling pathway in human cells
(a) Describe the differences between the groups of the amino acids located in the transmembrane domains and
those located in the amino- or carboxy-terminus of
. Describe the specific location in the cell where
protein is synthesized.
(b) The
progression.
protein leads to the inhibition of cyclin activity. Explain how this interferes with cell cycle
from being phosphorylated. Predict the effect of this
(c) Researchers discover a mutation that prevents
mutation on apoptosis by the pathway shown in Figure 2. Provide reasoning to justify your prediction.
(d) The drug cyclosporin is known to inhibit calcineurin. Researchers claim that cyclosporin should not be
given to patients with cancer. Support the researchers' claim based on the pathway shown in Figure 2.
AP Biology
Page 3 of 3