Download All normal, healthy body cells have MHC

4.9 B: Basic Cell Communication in Organ Systems Quiz
1.
PROCTOR VERSION
All normal, healthy body cells have MHC-1 proteins on their cell surfaces. A natural killer (NK) cell
is produced by the immune system and has inhibitory receptors that bind to MHC-1 proteins.
When an NK cell binds to a normal body cell, it recognizes the MHC-1 protein, “turns off,” and
does not destroy the cell. If, however, the NK cell binds to a cell lacking the correct MHC-1
protein, the NK cell is “turned on.” Different receptors on the NK cell then search for other
proteins that indicate that the cell is in distress or damaged. If these other proteins are detected,
the NK cell will release cytotoxic substances that destroy the distressed or damaged cell. The
diagrams below show how an NK cell interacts with a normal body cell and with a cancer cell
(damaged body cell).
Which condition most likely results in an autoimmune disorder that would cause NK cells to
attack and destroy normal, healthy body cells?
(A) A mutation makes the MHC-1 receptor on NK cells unable to “turn on” after the NK cells bind
to MHC-1 proteins on normal body cells.
Distractor Rationale:
This answer suggests the student may understand that NK cells must be “turned on” before
they destroy a distressed or damaged cell, but does not understand that binding to the
MHC-1 sites keeps NK cells inactive (“turned off”).
(B) Body cells are unable to produce MHC-1 proteins on the surface and have unique surface
proteins that cause NK cells to bind to them and “turn on.”
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4.9 B: Basic Cell Communication in Organ Systems Quiz
PROCTOR VERSION
Rationale:
This answer suggests the student understands that NK cells “turn on” and destroy
distressed or damaged cells that lack MHC-1 proteins and have unique surface proteins
indicating distress or damage.
(C) Body cells display abnormal MHC-1 proteins on their surface and NK cells have a mutation
that blocks their ability to produce cytotoxic substances.
Distractor Rationale:
This answer suggests the student may understand that NK cells will “turn on” when they
bind to cells that lack MHC-1 proteins, but does not understand that NK cells need to make
cytotoxins in order to destroy a distressed or damaged cell.
(D) A mutation prevents the MHC-1 receptors on NK cells from recognizing MHC-1 proteins and
prevents them from making receptors to detect other proteins.
Distractor Rationale:
This answer suggests the student may understand that NK cells will “turn on” when they
bind to cells that lack MHC-1 proteins, but does not understand that NK cells need to
detect other proteins before they destroy a distressed or damaged cell.
Aligned to: LO 4.9 CA 4.9: Predict Effects of Changes to Biological Systems
2.
The diagram below shows two pathways by which hormone A and hormone B are transported
from a secretory cell to a target cell.
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4.9 B: Basic Cell Communication in Organ Systems Quiz
PROCTOR VERSION
Which statement best explains why the two hormones are transported by different methods from
the secretory cell to the target cell?
(A) Hormone B can easily pass through the target cell’s membrane because it is a small
molecule, and hormone A must be transported through the target cell’s membrane because
it is a large molecule.
Distractor Rationale:
This answer suggests the student may understand that small molecules can pass more
easily through cell membranes than large molecules, but does not understand that
hormone A cannot be transported across the cell membrane because it is a water-soluble
hormone that cannot diffuse through the hydrophobic lipid membrane.
(B) Hormone A is a peptide because it binds to a surface protein on the target cell, and hormone
B is a nucleic acid because it travels into the nucleus and interacts with a gene.
Distractor Rationale:
This answer suggests the student may understand that hormone A could be a peptide
because it binds to surface receptors and that hormone B interacts with a gene in the
nucleus, but does not understand that hormone B could not be a nucleic acid because
nucleic acids are not a type of hormone, or that hormone B is lipid-soluble and can pass
through the lipid bilayer.
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4.9 B: Basic Cell Communication in Organ Systems Quiz
PROCTOR VERSION
(C) Hormone B is moved through the blood via carrier proteins because its receptor is in the
target cell’s nucleus, and hormone A travels freely through the blood to the target cell
because its receptor is on the target cell’s membrane.
Distractor Rationale:
This answer suggests the student may understand that hormone B binds to receptors in the
nucleus and must be transported by a protein, but does not understand that hormone B is
lipid-soluble and needs a carrier protein for transport in the blood, or that hormone A is
water-soluble and cannot diffuse across the target cell’s hydrophobic membrane.
(D) Hormone A does not need a carrier protein because it is a water-soluble hormone, and
hormone B must be transported through the blood via carrier proteins because it is a lipidsoluble hormone.
Rationale:
This answer suggests the student understands that hormone A is water-soluble and cannot
diffuse across the target cell’s hydrophobic membrane because the plasma membrane is
made of lipids, and that hormone B is lipid-soluble and can diffuse across the plasma
membrane but must be carried via transport proteins through the blood.
Aligned to: LO 4.9 CA 4.9: Predict Effects of Changes to Biological Systems
3.
Macrophages are large white blood cells that can engulf foreign substances called antigens. Both
macrophages and lymphocytes, such as T cells, appear together at the site of infection. Which
statement best explains how macrophages initiate an immune response when a new antigen is
first encountered?
(A) Macrophages incorporate the antigen into their genetic material and produce a large number
of identical macrophages that are programmed to destroy that specific antigen.
Distractor Rationale:
This answer suggests the student may understand that cells programmed to identify specific
antigens are copied in an immune response, but does not understand that B cells identify
antigens and produce plasma cells that release antibodies to destroy the antigen.
(B) Macrophages present the antigen directly to a memory B cell that produces antibodies
programmed to destroy that specific antigen.
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4.9 B: Basic Cell Communication in Organ Systems Quiz
PROCTOR VERSION
Distractor Rationale:
This answer suggests the student may understand how an immune response would occur
with a previous exposure, but does not understand that memory B cells would not be
present upon a first exposure to an antigen.
(C) Macrophages present the antigen to helper T cells, which activate memory B cells to
produce plasma cells, and the plasma cells release antibodies that identify and destroy that
specific antigen.
Rationale:
This answer suggests the student understands how macrophages work with helper T cells
to initiate an immune response by activating B cells to produce plasma cells, which release
antibodies that destroy the specific antigen.
(D) Macrophages present fragments of the antigen to other macrophages, which are then able
to seek out and destroy the antigen by releasing helper T cells that engulf that specific
antigen.
Distractor Rationale:
This answer suggests the student may understand how macrophages break down antigens
and present them to the immune system, but does not understand that macrophages
present antigen fragments to helper T cells, which activate B cells, and that B cells produce
plasma cells that release antibodies to destroy the antigen.
Aligned to: LO 4.9 CA 4.9: Predict Effects of Changes to Biological Systems
4.
Nerve cells communicate with one another via chemical messengers called neurotransmitters.
Endorphins are a type of neurotransmitter that decrease pain signals by interacting with the
sodium (Na+) channels and potassium (K+) channels in a postsynaptic nerve cell. Which
statement describes how an endorphin most likely interacts with a postsynaptic neuron in a pain
signal pathway?
(A) Endorphins bind to and temporarily close sodium (Na+) channels in the postsynaptic neuron,
which prevents depolarization of the neuron.
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4.9 B: Basic Cell Communication in Organ Systems Quiz
PROCTOR VERSION
Rationale:
This answer suggests the student understands that opening sodium (Na+) channels is
required for an action potential and that a neurotransmitter that prevents this would inhibit
the signal.
(B) Endorphins bind to and temporarily open potassium (K+) channels in the postsynaptic
neuron, which represses all neural activity.
Distractor Rationale:
This answer suggests the student may understand that open potassium (K+) channels may
affect the ability of a nerve cell to send a signal, but does not understand that opening
potassium channels would not repress all neural activity because potassium channels are
opened at the end of the action potential (after sodium ions have entered the cell) and a
temporary opening causes hyperpolarization for a short while until the potassium channels
close again and the resting potential is reestablished, allowing the cell to experience another
action potential.
(C) Endorphins bind to and permanently open sodium (Na+) channels in the postsynaptic
neuron, which decreases the membrane potential of the neuron.
Distractor Rationale:
This answer suggests the student may understand that opening sodium (Na+) channels
causes the depolarization of the neuron, but does not understand that permanently
opening sodium channels will render the cell unable to function for any nerve signals, not
just pain signals, and this will lead to the death of the organism.
(D) Endorphins bind to and permanently disable the potassium (K+) channels in the
postsynaptic neuron, which prevents the neuron from reaching an action potential.
Distractor Rationale:
This answer suggests the student may understand that disabling the potassium (Na+/K+)
channels would prevent an action potential, but does not understand that this would
permanently disable the pain signal pathway after the endorphins are removed.
Aligned to: LO 4.9 CA 4.9: Predict Effects of Changes to Biological Systems
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