Skip to ContentGo to accessibility pageKeyboard shortcuts menu
OpenStax Logo
Biology for AP® Courses

Test Prep for AP® Courses

Biology for AP® CoursesTest Prep for AP® Courses
43 .
A pathogenic bacterium has been engulfed by a phagocytic cell as part of the innate immune response. Which of the following illustrations best represents the response? [source: AP Biology Course and Exam Description Fall 2012, p. 132]
  1. An irregularly-shaped phagocytic cell with many protrusions along its surface has a rod-shaped bacterium within an invagination at its upper right. An arrow points from this bacterium to a similar bacterium that is fully enclosed in membrane within the bacterium. To the upper and lower left of this structure, there are horizontal discs along the membrane with ovals above, labeled ribosomes, from which blue strands emerge and coil down to the sides to extend into the membranous structure around the bacterium. At the lower left, a similarly-shaped membrane contains many small dots and an arrow points to an opening formed by an invagination in the membrane that contains many small dots leaving the cell.
  2. An irregularly-shaped phagocytic cell with many protrusions along its surface has a rod-shaped bacterium within an invagination at its upper right. An arrow points from this bacterium to a similar bacterium that is fully enclosed in membrane within the bacterium. Two
  3. An irregularly-shaped phagocytic cell with many protrusions along its surface has a rod-shaped bacterium within an invagination at its upper right. An arrow points from this bacterium to a similar bacterium that is fully enclosed in membrane within the bacterium. Arrows point from this membrane-enclosed bacterium and from a nearby circular lysosome containing many small dots inside to show that the two come together with the lysosome adjacent to the right side of the bacterium. At the lower left, a similarly-shaped membrane contains many small dots and an arrow points to an opening formed by an invagination in the membrane that contains many small dots leaving the cell.
  4. An irregularly-shaped phagocytic cell with many protrusions along its surface has a rod-shaped bacterium within an invagination at its upper right. An arrow points from this bacterium to a similar bacterium that is fully enclosed in membrane within the bacterium. Arrows point from this membrane-enclosed bacterium and from a nearby mitochondrion, shown as an oval with short lines extending from both sides along its width toward its center, to show that the two come together with the end of the mitocondrion adjacent to the upper left of the bacterium. At the lower left, a similarly-shaped membrane contains many small dots and an arrow points to an opening formed by an invagination in the membrane that contains many small dots leaving the cell.
44 .
How do natural killer cells react to healthy cells compared to cells infected with a pathogen?
  1. Natural killer cells recognize MHC I on a healthy cell and do not kill it, while the infected cells that do not present MHC I are killed.
  2. Natural killer cells recognize MHC I on an infected cell and kill it, while the healthy cells that do not present MHC I are not killed.
  3. Natural killer cells recognize MHC II on a healthy cell and do not kill it, while the infected cells that do not present MHC II are killed.
  4. Natural killer cells recognize MHC II on an infected cell and kill it, while the healthy cells that do not present MHC II are not killed.
45 .

The flow diagram shows four boxes connected by arrows. The first box is labeled A and reads: PAMPs. An arrow then leads to the second box labeled B, which reads: PRRs. An arrow then leads to the third box, which reads: Cytokines. An arrow then leads to the fourth box labeled C, which reads: Reduced gene expression, protein synthesis.

The following incomplete diagram represents a series of events during an innate immune response. The labels A, B, and C need to be replaced with the names of the cells involved. Which set of cells correctly completes this diagram?

  1. A = infected host cell, B = pathogen, C = healthy host cell
  2. A = healthy host cell, B = pathogen, C = dendritic cell
  3. A = dendritic cell, B = infected host cell, C = pathogen
  4. A = pathogen, B = dendritic cell, C = healthy host cell
46 .
A healthy person produces antibodies to pathogens that invade the body. However, if this person becomes infected with HIV, the body loses the ability to produce antibodies. Research has shown that the virus attacks and destroys CD4+T cells. Why does destruction of CD4+T cells lead to a loss of antibody synthesis in HIV-infected patients?
  1. CD4+T cells are a required intermediate in a series of cell-to-cell signaling events that must be completed before B cells can mature.
  2. CD4+T cells have CD4 molecules covalently bound to their cell surfaces and do not induce apoptosis in other cells during an immune response.
  3. CD4+T cell counts are about 1,000 per microliter in a healthy person, but drop below 400 per microliter in a person who cannot mount an immune response.
  4. CD4+T cell precursors are formed in the bone marrow and then migrate to the thymus, where they develop their T cell receptors.
47 .
Which of the following diagrams best illustrates how a macrophage activates a helper T cell (THcell)?
  1. An irregularly-shaped cell labeled macrophage has a smooth, oval nucleus containing a small dark circle and is adjacent to a smooth, circular T H cell with a similar nucleus. An arrow points downward to show that the two cells come together so that a protrusion from the right side of the macrophage touches the left side of the T H cell.
  2. An irregularly-shaped cell labeled macrophage has a smooth, oval nucleus containing a small dark circle and is adjacent to a smooth, circular T H cell with a similar nucleus and with a rectangular protrusion from its left side. The rectangular protrusion has a highlighted tip. An arrow points downward to show that the two cells come together so that a protrusion from the right side of the macrophage touches the tip of the protrusion from the left side of the T H cell.
  3. An irregularly-shaped cell labeled macrophage has a smooth, oval nucleus containing a small dark circle. A protrusion from its right side has a horizontal bar above a “Y”-shaped antibody with its fork extending out of the cell. The macrophage is adjacent to a smooth, circular T H cell with a similar nucleus and with a rectangular protrusion from its left side. The rectangular protrusion has a highlighted tip. An arrow points downward to show that the two cells come together so that the fork of the antibody from the right side of the macrophage encloses the tip of the protrusion from the left side of the T H cell.
  4. An irregularly-shaped cell labeled macrophage has a smooth, oval nucleus containing a small dark circle. A rectangular protrusion with a circle on its right end extends from a two-part protrusion of the membrane on the right side of the macrophage. To the right, a smooth, circular T H cell with a similar nucleus has a horizontal protrusion from its left side above a “Y”-shaped antibody that extends from the cell membrane with its fork facing outward. An arrow points downward to show that the circle from the macrophage is enclosed within the fork of the antibody of the T H cell.
48 .

The graph plots antibody titer on the y-axis versus time on the x-axis. An arrow with the label vaccination appears at 0 on the x-axis. A red line labeled IgM shows a dramatic peak at 10–14 days. A blue line labeled IgG shows a much less dramatic arc with its peak at a slightly later time interval.

The graph shows changes in a person’s blood after they receive a vaccination. Explain how cell communication is involved in bringing about the changes depicted in the graph.

  1. The vaccine introduces antigens specific to a pathogen into the person’s blood. These antigens are moved to the cell surface of antigen-presenting cells present in the blood. Receptors on helper T cells bind to the antigens present on the antigen-presenting cell. This direct cell-to-cell contact initiates a series of events that leads to production of antibodies by B lymphocytes.
  2. The vaccine introduces antigens specific to a pathogen into the person’s blood. These antigens bind to the receptors on the surface of T cells. This direct cell-to-cell contact initiates a series of events that leads to production of antibodies by B lymphocytes.
  3. The vaccine introduces antigens specific to a pathogen into the person’s blood. These antigens are moved to the cell surface of antigen-presenting cells present in the blood. This direct cell-to-cell contact initiates a series of events that leads to production of antibodies by B lymphocytes.
  4. The vaccine introduces antigens specific to a pathogen into the person’s blood. These antigens are moved to the cell surface of antigen-presenting cells present in the blood. Receptors on helper T cells bind to the antigens present on the antigen-presenting cell. This direct cell-to-cell contact initiates a series of events that activates the complement system.
49 .
B cells are important immune cells that fight infections. How is a naïve B cell stimulated to mature into a plasma cell that secretes antibodies?
  1. T cells secrete cytokines, which help the B cell to multiply and mature into an antibody-producing plasma cell.
  2. Natural killer cells secrete cytokines, which help the B cell to multiply and mature into an antibody-producing plasma cell.
  3. T cells secrete interferons, which help the B cell to multiply and mature into an antibody-producing plasma cell.
  4. Natural killer cells secrete interferons, which help the B cell to multiply and mature into an antibody-producing plasma cell.
50 .

The illustration shows bacterial toxins encountering a host cell with toxin receptors. It then shows antibodies bound in complex to the toxins outside of the host cell.

The diagram illustrates a process taking place during an immune response.

Which option describes what is happening in this diagram?

  1. The antibodies bind to bacteria, preventing them from dividing.
  2. The antibodies bind to bacteria, facilitating their consumption by a macrophage.
  3. The antibodies bind to toxic molecules released by bacteria, preventing them from entering cells.
  4. The antibodies bind to toxic molecules released by bacteria, stopping their movement through the body.
51 .

The flow diagram shows a mouse embryo not making Ig on the left and a mouse B cell tumor making a specific light chain on the right. Arrows from each cell lead to a box that reads: DNA extracted and digested with restriction enzyme. Arrows then point to a box that reads: DNA restriction fragments separated by electrophoresis. Arrows then point to a box that reads: V- and C-region coding sequences visualized by hybridization with radioactive DNA probes. The left arrow then points to an illustration showing V- and C-region coding sequences on separate fragments. The right arrow then points to an illustration showing V- and C-region coding sequences on the same fragment.

Scientists performed an experiment using a cell from a mouse embryo and a B cell from an adult mouse. The mouse embryo cell does not make antibodies, yet its DNA contains nucleotide sequences encoding antibody polypeptides. The adult mouse B cell makes and secretes a single type of antibody. In the experiment, radiolabeled DNA probes were synthesized to be complementary to the DNA encoding the light chains of antibody produced by the adult mouse B cells. Then, DNA from the mouse embryo cell and from the adult B cell were isolated and tested to see if either hybridized with the synthesized radiolabeled DNA probes. The results are shown in the diagram. Which claim is best supported by the data?

  1. The mouse genome contains an enormous number of antibody genes, which accounts for the huge diversity of antibody molecules that can be made.
  2. Rearrangement of gene segments encoding antibody polypeptides occurs at the level of DNA to produce an enormous diversity of antibody molecules.
  3. The tremendous diversity of antibody molecules that can be made results from post-translational modifications of antibody polypeptide chains.
  4. Each antibody is encoded by its own unique gene in the DNA, which explains how antibodies can have different antigen binding properties.
52 .
How does an antibody molecule bind specifically to one antigen but not to others?
  1. due to the presence of a specific antigen binding site
  2. due to the constant region
  3. due to diversity of variable region
  4. due to the complete antibody structure
53 .
The human genome contains less than 50,000 genes, yet a human has the capability of producing more than 1012different antibody molecules. How can this evidence be used to support the claim that the human body has an immune system that is both effective and efficient?
  1. There are so many different antibody molecules that can be made, each of which can specifically target a particular pathogen to destroy it. This specificity makes the immune system more effective. The immune system is also efficient because each antibody need to have its own gene.
  2. There are so many different antibody molecules that can be made, each of which can non-specifically target a particular pathogen to destroy it. This non-specificity makes the immune system more effective. The immune system is also efficient because each antibody does not need to have its own gene.
  3. There are so many different antibody molecules that can be made, each of which can specifically target a particular pathogen to destroy it. This specificity makes the immune system more efficient. The immune system is also effective because each antibody does not need to have its own gene.
  4. There are so many different antibody molecules that can be made, each of which can specifically target a particular pathogen to destroy it. This specificity makes the immune system more effective. The immune system is also efficient because each antibody does not need to have its own gene.
54 .

The illustration shows a mast cell producing histamine. Histamine receptors are shown on vessel cells and nerve cells with anti-histamine bound to the histamine receptors.

An allergy is caused by the immune system reacting to a foreign protein to produce IgE molecules that recognize the protein. These IgE molecules become associated with mast cells that respond to future exposures to the protein by releasing histamines into the body. The diagram shows this release and also shows how a drug called an antihistamine can help an allergy sufferer reduce their allergy symptoms. Which of the following statements explains how an antihistamine helps restore homeostasis during an allergic reaction?

  1. Antihistamines prevent mast cells from becoming associated with IgE molecules that recognize the foreign protein allergen.
  2. Antihistamines prevent mast cells from releasing histamines and causing the unpleasant allergy symptoms.
  3. Antihistamines prevent histamines that have been released by mast cells from stimulating the itching and swelling of body tissues.
  4. Antihistamines prevent mast cells from producing histamines, which halts their effect on the body.
55 .

The illustration shows the pituitary gland secreting TSH, which binds to a TSH receptor on a thyroid cell. This then stimulates hormone synthesis and the regulated production of thyroid hormones, which are connected to the pituitary gland under negative feedback control.

The diagram shows the normal feedback loop that controls the production of thyroid hormones in the human body. Graves’ disease is an autoimmune disease in which the body produces autoantibodies to the TSH receptor. When these autoantibodies bind to the receptor, it mimics the action of the TSH hormone. How would the feedback loop and the regulated production of thyroid hormones shown in the diagram be affected in a person with Graves’ disease?

  1. The feedback loop would be disrupted. Autoantibodies would bind to the TSH receptors, allowing them to continue to produce thyroid hormones. As a result, there would be an overproduction of thyroid hormones because the negative feedback system would be unable to function.
  2. The feedback loop would be not be disrupted. Autoantibodies would bind to the TSH receptors, allowing them to continue to produce thyroid hormones. As a result, there would be an overproduction of thyroid hormones because the negative feedback system would be unable to function.
  3. The feedback loop would be disrupted. Autoantibodies would not bind to the TSH receptors, allowing them to continue to produce thyroid hormones. As a result, there would be an overproduction of thyroid hormones because the negative feedback system would be unable to function.
  4. The feedback loop would be disrupted. Autoantibodies would bind to the TSH receptors, allowing them to continue to produce thyroid hormones. As a result, there would be an overproduction of thyroid hormones because the negative feedback system was functional.
56 .

A pair of figures show the release of acetylcholine from a nerve cell to bind with acetylcholine receptors of a muscle cell and a similar illustration in which auto-antibodies to acetylcholine receptors prevent acetylcholine from binding. The upper illustration shows the lower left of an oval structure labeled nerve that contains three intact circles each containing five to six small circles. There are two similar circles that have fused with the bottom membrane of the nerve cell to begin to release the small circles within, labeled acetylcholine, into a gap below. Beneath the gap, there is the folded upper membrane of a muscle cell. The muscle cell has three protrusions into the gap with invaginations between them. The top of each protrusion has an oval structure with circular cutouts on top. These oval structures are labeled acetylcholine receptors. The oval structure at the upper left is small with cutouts containing two molecules of acetylcholine and the ovals above center and right-hand protrusions are larger and are each bound to four acetylcholine molecules. Seven acetylcholine molecules are loose within the gap. The bottom illustration is similar except that there are five “Y”-shaped auto-antibodies to acetylcholine receptors within the gap preventing acetylcholine from binding. The left-hand acetylcholine receptor forms a crescent with the fork of an auto-antibody above it. The center and right-hand acetylcholine receptors each have two auto-antibodies above them with the auto-antibody forks enclosing protrusions and extending to fill four of the cutouts into which acetylcholine would otherwise bind.

Myasthenia gravis is an autoimmune disease that initially presents with muscle weakness and can progress to complete impairment of muscle movement. The diagram compares a healthy individual with an individual suffering from this disease. Which statement best explains what happens to bring about this disease?

  1. The body produces antibodies against nerve cells, which prevents the nerve cells from releasing acetylcholine during signal transmissions to muscle.
  2. The body produces antibodies against acetylcholine, which prevents acetylcholine from transmitting signals from nerves to muscle.
  3. The body produces antibodies against receptors in muscle, which prevents acetylcholine from binding and completing nerve signal transmission.
  4. The body produces antibodies against acetylcholine, which prevents acetylcholine from breaking down after signal transmission is complete.
PreviousNext
Order a print copy
Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution License and you must attribute OpenStax.

Attribution information
  • If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:
    Access for free at https://openstax.org/books/biology-ap-courses/pages/1-introduction
  • If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:
    Access for free at https://openstax.org/books/biology-ap-courses/pages/1-introduction
Citation information

© Sep 19, 2024 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.