unit 3 week 4 homework
Your patient is living with HIV infection and has not developed AIDS. She knows that her CD4 count is carefully monitored, and she asks why this test is important. How would you explain the role of CD4 cells? "CD4 cells attack and kill bacteria as they enter the body." "CD4 cells produce antibodies that disable antigens if they breach the body's first line of defense." "CD4 cells produce complement, which enhances several processes in the immune response." "CD4 cells are special lymphocytes (white blood cells) that activate other immune cells and direct your body's response to invaders."
"CD4 cells are special lymphocytes (white blood cells) that activate other immune cells and direct your body's response to invaders."
What type of cell is the precursor to the helper T cell? regulatory T cell CD4 cell CD8 cell memory T cell
CD4 cell
Which type of chemical induces fever? antibodies interferon complement pyrogens
pyrogens
Class I MHC proteins are recognized by which of the following cell types (that are destined to become T cells)? CD4 CD8
CD8
Which major class of lymphocytes become cytotoxic T cells? CD8 cells CD4 cells CD6 cells
CD8 cells
Which of the following is characteristic of complete antigens? contain many repeating chemical units small molecules inhibit production of antibodies reactivity with an antibody
reactivity with an antibody
Which of the following statements is incorrect or false? Haptens lack immunogenicity unless attached to protein carriers. Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens. Class I MHC molecules are built into the plasma membranes of all body cells. MHC proteins are the cell's identity markers.
Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens.
A person who has AIDS contracts rare and often life-threatening infections because their helper T cell count is so low. Which of the following components of the immune response still respond to antigen despite the low helper T cell count? Apoptosis of infected host cells Clonal expansion and antibody production Clonal selection of B cells Activation of cytotoxic T cells
Clonal selection of B cells
A person who has AIDS contracts rare and often life-threatening infections because their helper T cell count is so low. Which of the following components of the immune response still respond to antigen despite the low helper T cell count? Apoptosis of infected host cells Clonal selection of B cells Activation of cytotoxic T cells Clonal expansion and antibody production
Clonal selection of B cells
Cancer cells would be attacked by which of the following cells? Cytotoxic T cells macrophages B cells
Cytotoxic T cells
How do cytotoxic cells directly attack target cells? Cytotoxic cells release antibodies that track down foreign cells and destroy them. Cytotoxic cells engulf target cells via phagocytosis. Cytotoxic cells release complement proteins that weaken pathogen cell membranes and amplify the immune response. Cytotoxic cells bind to the target cell and secrete chemicals that induce apoptosis.
Cytotoxic cells bind to the target cell and secrete chemicals that induce apoptosis.
Which of the following should produce naturally acquired, active immunity? drinking breast milk recovering from the chicken pox injections of antibody produced by a goat getting a flu vaccine
recovering from the chicken pox
Tissue rejection after an organ transplant is least likely due to the action of _________. macrophages cytotoxic T cells regulatory T cells natural killer cells
regulatory T cells
Which of the following is NOT a function of the inflammatory response? disposes of cellular debris and pathogens replaces injured tissues with connective tissues sets the stage for repair processes prevents the spread of the injurious agent to nearby tiss
replaces injured tissues with connective tissues
Clonal selection of B cells ________. .occurs during fetal development cannot occur in the presence of antigens results in the formation of plasma cells only occurs in the secondary immune response
results in the formation of plasma cells
Cilia and mucous are examples of which line of defense? First line of defense Second line of defense Third line of defense
First line of defense
What is the role of helper T cells in the adaptive immune response? Helper T cells directly kill infected host cells. Helper T cells phagocytize bacteria and viruses. Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells. Helper T cells produce and secrete antibodies.
Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells.
What is the role of helper T cells in the adaptive immune response? Helper T cells phagocytize bacteria and viruses. Helper T cells produce and secrete antibodies. Helper T cells directly kill infected host cells. Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells.
Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells.
A person with a deficit of IgA is likely to exhibit recurrent respiratory tract infections. Which of the following correctly explains the role of IgA in this scenario? IgA functions as a B cell antigen receptor; without these receptors B cells are unable to protect us against pathogens on our body surfaces IgA, found in the mucus lining of the respiratory tract, helps stop pathogens from attaching to epithelial surfaces and entering our body IgA triggers release of histamine from cells in our mucous membranes, which is required for an inflammatory response to infection IgA is the most abundant antibody in the plasma and plays a central role in protecting against bacterial infections on our body surfaces
IgA, found in the mucus lining of the respiratory tract, helps stop pathogens from attaching to epithelial surfaces and entering our body
Which of the following are properly matched? IgA: first antibody released during primary immune response IgG: most abundant antibody IgM: secreted in tears IgE: main antibody of the secondary immune response
IgG: most abundant antibody
How do interferons protect against viral infection in healthy cells? Interferons encourage the production of antiviral proteins. Interferons promote fever, or an abnormally high body temperature. Interferons activate complement. Interferons perform opsonization to coat microorganisms.
Interferons encourage the production of antiviral proteins.
What types of antigen do mature T cells normally not recognize? processed fragments of protein antigens displayed on surfaces of body cells cancer antigens bacterial antigens self-antigens
self-antigens
The student who caught the cold caused by this specific Rhinovirus was exposed to the exact same Rhinovirus 18 months later. What component of the immune system will protect her from getting the same cold again? Memory B cells Dendritic cells Plasma cells Antibodies that are "left over" from the last infection
Memory B cells
The student who caught the cold caused by this specific Rhinovirus was exposed to the exact same Rhinovirus 18 months later. What component of the immune system will protect her from getting the same cold again? Memory B cells Plasma cells Antibodies that are "left over" from the last infection Dendritic cells
Memory B cells
What roles do memory B cells play when a patient is re-exposed to an antigen? Memory B cells trigger a secondary immune response, which is faster, more prolonged, and more effective than the first immune response. Memory B cells activate helper T cells, which, in turn, activate CD8 cells. Memory B cells trigger a secondary immune response that is slower and less effective than the primary immune response. Due to previous exposure, memory B cells are able to quickly recognize invading pathogens, dock with them, and induce apoptosis.
Memory B cells trigger a secondary immune response, which is faster, more prolonged, and more effective than the first immune response.
Which of the following is NOT a property of mucous membranes? Mucous membranes produce defensins that can damage pathogen cell membranes. Mucus contains lysozymes that destroy bacteria. Mucin in mucus allows it to trap pathogens. Mucus contains macrophages that attack invading pathogens.
Mucus contains macrophages that attack invading pathogens.
Which of the following statements regarding NK cells is a false or incorrect statement? NK cells attack cells that display abnormal MHC or lack MHC antigens. NK cells are present in the blood, spleen, lymph nodes, and red bone marrow. NK cells are a type of neutrophil. NK cells attack cancer cells and virus-infected body cells.
NK cells are a type of neutrophil.
Which of the following is NOT a characteristic of Natural Killer (NK) cells? NK cells induce the target cell to undergo "apoptosis" (cell suicide). NK cells attack transplanted organs. NK cells recognize abnormal or cancer cells by a specific antigen on their cell membrane. NK cells attack infected or cancerous cells.
NK cells recognize abnormal or cancer cells by a specific antigen on their cell membrane.
What characterizes the chemotaxis phase of phagocyte mobilization? Neutrophils and other WBCs migrate up the gradient of chemotactic agents to the site of injury. Neutrophils flatten to squeeze between the endothelial cells of the capillary walls. Neutrophils cling to the inner walls of capillaries and postcapillary venules. Neutrophils actively ingest bacteria.
Neutrophils and other WBCs migrate up the gradient of chemotactic agents to the site of injury.
Select the correct statement about antigens. "Self-antigens" is another name for incomplete antigens. Only small antigens exhibit reactivity. One antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody. The largest type of antigen is called a hapten.
One antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody.
Antibodies are produced from which cells? Helper T (TH) cells' CD8 cells Plasma cells Dendritic cells
Plasma cells
Which is a part of the innate immune defenses? skin antibodies T cells B cells
skin
Which of the following provides a first line of defense against pathogens? skin and mucous membranes complement antimicrobial proteins inflammation
skin and mucous membranes
What is the role of interferon? Initiate the inflammatory response Form membrane attack complexes Prevent further viral replication Phagocytize foreign bacteria
Prevent further viral replication
Which of the following is NOT a step used by cytotoxic T cells to kill infected host cells? Recognition of infected host cell using its CD4 glycoprotein Secretion of perforin Secretion of granzyme Recognition of infected host cell using its TCR
Recognition of infected host cell using its CD4 glycoprotein
Which of the following is NOT a step used by cytotoxic T cells to kill infected host cells? Secretion of perforin Recognition of infected host cell using its TCR Secretion of granzyme Recognition of infected host cell using its CD4 glycoprotein
Recognition of infected host cell using its CD4 glycoprotein
Natural killer (NK) cells and the inflammatory response are examples of which line of defense? First line of defense Second line of defense Third line of defense
Second line of defense
Which of the following is not an antigen-presenting cell (APC)? macrophage dendritic cell B cell T cell
T cell
Which of the following is/are the most specific internal defense against disease? inflammation NK cells phagocytes T cells
T cells
Without the positive selection process in lymphocyte maturation ________. autoimmune diseases would be likely to result T cells would not be able to properly bind to APC's and therefore not be activated by them NK cells would be non-functional monocytes would not be able to migrate into infected tissue and differentiate into macrophages
T cells would not be able to properly bind to APC's and therefore not be activated by them
Which of the following does NOT correctly describe the process of CD4 T cell activation and proliferation? The CD4 T cell's antigen receptor binds to an antigen displayed on an MHC on the surface of an antigen presenting cell. In order to proliferate and form clones, the CD4 T cell must receive cytokines released by antigen presenting cells or T cells. The CD4 T cell's antigen receptor binds to a class I MHC on the surface of an antigen presenting cell. Co-stimulatory molecules on the surface of the antigen presenting cell bind to specific receptors on the CD4 T cell.
The CD4 T cell's antigen receptor binds to a class I MHC on the surface of an antigen presenting cell.
What occurs if a naïve T cell binds to an antigen without receiving a co-stimulatory signal? The T cell releases interleukins.T he T cell becomes a memory cell. The T cell enters a state of anergy. The T cell is activated.
The T cell enters a state of anergy.
Your clinical instructor wants a brief description of the four cardinal signs of inflammation. What would you tell him? The infectious particles are directly responsible for the signs of inflammation The heat and redness are caused by increased blood flow to the infected areas, and the pain and swelling are caused by excessive leakage of fluid from the capillaries into the infected area. The infection is making your body produce more heat and blood. The heat and redness are because of fever, and the pain and swelling are your created by your brain.
The heat and redness are caused by increased blood flow to the infected areas, and the pain and swelling are caused by excessive leakage of fluid from the capillaries into the infected area.
Which of the following statements does NOT accurately describe a difference between the innate and adaptive defenses of the body? Innate defenses tend to occur much faster than adaptive defenses. Innate defenses involve physical barriers, cells, bloodborne chemicals, and inflammatory responses, while adaptive defenses primarily utilize lymphocytes and antibodies. The innate defenses of the body apply strictly to external pathogens, while adaptive defenses apply strictly to internal pathogens. Any foreign substances may activate the innate defenses, while adaptive defenses are specific to the type of invading pathogen.
The innate defenses of the body apply strictly to external pathogens, while adaptive defenses apply strictly to internal pathogens.
How do phagocytes recognize foreign cells or bacteria? All the foreign cells or bacteria are marked with opsonins that the phagocytes recognize. The phagocytes look for the absence of "self" proteins. Phagocytes recognize a specific antigen on the cell surface. The phagocytes recognize molecules on pathogens not normally found on body cells.
The phagocytes recognize molecules on pathogens not normally found on body cells.
Part complete In order for interferons to protect healthy cells, they must first bind to _________. the membrane receptors on healthy cells the immature viruses in infected cells the DNA of healthy cells the DNA of the cell making the interferon
the membrane receptors on healthy cells
How is the adaptive third line of defense able to target specific pathogens? The third line of defense responds to antigens on the pathogen. The third line of defense activates natural killer cells that hunt down and selectively destroy pathogens. The third line of defense responds to antibodies produced by the pathogen. The third line of defense triggers inflammation, which mobilizes a specific attack on the invading pathogen.
The third line of defense responds to antigens on the pathogen.
Which of the following is NOT a chemical barrier that helps prevent infections? mucus tears the pH of the blood pH of the urine
the pH of the blood
Which statement is true about T cells? Their proliferation is enhanced by interleukins 1 and 2. They will develop into cytotoxic T cells if antigen is complexed with class II MHC proteins. Once activated, they cannot secrete cytokines. They usually directly recognize antigens, which then activates a subpopulation of killer cells.
Their proliferation is enhanced by interleukins 1 and 2.
B lymphocytes are categorized as part of the adaptive branch of the immune system for all of the following reason but one. Which of the following is NOT one of the reasons B lymphocytes are considered part of the adaptive immunity? They require costimulation from an activated T helper cell. They produce memory cells when activated. Their receptors will bind to only one antigen. They are a first line of defense that can begin killing pathogens immediately.
They are a first line of defense that can begin killing pathogens immediately.
T cells are differentiated into two groups based on their glycoproteins: CD4 or CD8. Which of the following is true of CD4 T cells? They become cytotoxic T cells. They become T helper cells. They become plasma cells. They become antigen presenting cells (APC) cells.
They become T helper cells.
A vaccine is effective because ________. .the vaccine contains the antibodies necessary to fight infection the secondary response of the adaptive immunity is faster and more efficient than the primary response lymphocytes are unable to mount an immune response the first time they are exposed to a new pathogen the vaccine contains the lymphocytes necessary to fight infection
the secondary response of the adaptive immunity is faster and more efficient than the primary response
All but one of the following occurs during the inflammatory response. Select the example below that does NOT describe the process of inflammation. Inflammation increases capillary permeability. Release of prostaglandins results in pain. Vasoconstriction prevents excessive blood loss due to injury. Chemotaxis draws leucocytes to the site of injury.
Vasoconstriction prevents excessive blood loss due to injury.
Treatment of an abscess often requires that it be surgically drained because ______. the wall of the abscess prevents proper blood flow into the pus the wall of the abscess prevents proper elimination of wastes from the enclosed pus the wall of the abscess prevents neutrophils from entering the pus and attacking the pathogens the wall of the abscess prevents macrophages from differentiating into monocytes in the pus
the wall of the abscess prevents neutrophils from entering the pus and attacking the pathogens
Which of the following is NOT a mechanism for the development of autoimmune disorders? a second exposure to an allergen exposure of previously "hidden" self-antigens to the adaptive immune system during trauma cross-reaction of antibodies formed against foreign antigens (haptens) bound withself-antigens mutation followed by the appearance of membrane proteins not previously present
a second exposure to an allergen
Which specific type of cell produces antibodies? activated antigen-presenting cells activated plasma cells activated memory T cells activated helper T cells
activated plasma cells
Proliferation of lymphocytes occurs immediately after which of these events? entering the circulation activation release from the bone marrow seeding of secondary lymphoid organs
activation
Costanza was picking grapes in her father's arbor when she felt a short prickling pain in her finger. She ran crying to her father, who removed an insect stinger and calmed her with a glass of lemonade. Twenty minutes later Costanza's finger was red, swollen, and throbbing where she had been stung. What type of immune response was she exhibiting? subacute, type III hypersensitivity reaction acute, type I hypersensitivity reaction subacute, type II hypersensitivity reaction delayed, type IV hypersensitivity reaction
acute, type I hypersensitivity reaction
Which of the following types of cells display protein fragments produced by the cancer within them? macrophages all nucleated cells dendritic cells B cells
all nucleated cells
Allergens differ from antigens because ________. allergens do not involve the leucocytes, they simply stimulate the inflammatory response allergens produce an abnormally large immune response to what is an otherwise harmless particle allergens are primarily plant derived while antigens are bacterial or viral in nature allergens are only active seasonally and are generally harmless to the body
allergens produce an abnormally large immune response to what is an otherwise harmless particle
What is the name of the unique area (specific region) that a lymphocyte recognizes and binds to? pathogen antigen an antigenic determinant antibody
an antigenic determinant
Which molecules of the adaptive defense system provide humoral immunity by circulating freely in the blood and lymph, where they bind to extracellular antigens and inactivate them and mark them for destruction? interferons antigens antibodies complement proteins
antibodies
Which of the following chemicals do NOT directly trigger inflammation? kinins antibodies histamines prostaglandins
antibodies
Which of the following can act as opsonins on bacteria, thus enhancing phagocytosis? interferons natural killer (NK) cells T cells antibodies and complement protein
antibodies and complement protein
Which of the following best describes humoral immunity? activation of T cells in the lymphatic fluid mobilization of phagocytes antibodies being released in the body fluids edema and formation of exudate
antibodies being released in the body fluids
Immediate and subacute hypersensitivities are caused by ________ that trigger the release of _________. viruses; interferon antibodies; histamine memory B cells; antibodies memory T cells; perforins
antibodies; histamine
Which of the following events is not directly associated with inflammatory responses? antibody production phagocyte mobilization vasodilation increased vascular permeability
antibody production
T-cell activation requires ________. antigen binding and antibody production antigen binding and co-stimulation antibody production and co-stimulation antigen binding, antibody production, and co-stimulation
antigen binding and co-stimulation
Which of the following activate CD8 cells? antigens on class II MHC proteins peptides containing 14-17 amino acids antigen fragments on class I MHC proteins exogenous antigens
antigen fragments on class I MHC
Class II MHC proteins are found on which of the following cell types? antigen-presenting cells all nucleated cells
antigen-presenting cells
Which of the following is NOT a type of T cell? cytotoxic antigenic regulatory helper
antigenic
Vaccines provide what type of immunity? artificially acquired passive naturally acquired active artificially acquired active naturally acquired passive
artificially acquired active
T cells achieve self-tolerance in the __________. tonsils bone marrow thymus lymph nodes
thymus
Which of the following is NOT an event that can result in an autoimmune disease? activation of self-reactive lymphocytes that survived negative selection genetic mutations causing changes in the structure of self-antigens cross-reaction of antibodies produced against foreign antigens with self-antigens `` binding of a T cell to an antigen without receiving a co-stimulatory signal
binding of a T cell to an antigen without receiving a co-stimulatory signal
B lymphocytes develop immunocompetence in the ________. thymus bone marrow lymph nodes spleen
bone marrow
Inflammation ________. slows the healing process with swelling that can impair bodily function is caused by bacterial activity to enhance the spread of disease brings more leukocytes to the site of infection is caused by viral activity to enhance the spread of the disease
brings more leukocytes to the site of infection
Which of the following is NOT a typical sign of inflammation? redness heat swelling bruising
bruising
How does a lymphocyte exhibit immunocompetence? by being relatively unresponsive to self-antigens so that they do not attack the body's own cells by recognizing self-antigen by being able to recognize their one specific antigen by rapidly proliferating to form an army of cells exactly like themselves and bearing the same antigen-specific receptors
by being able to recognize their one specific antigen
How do natural killer cells destroy invading pathogens? by producing interferons that block the replication and spread of pathogens by producing antibodies that target cells for destruction by engulfing cells via phagocytosis by inducing apoptosis in the target cell
by inducing apoptosis in the target cell
What is the role of complement in the innate immune response? to amplify the inflammatory process to produce a fever to identify pathogens for phagocytosis by natural killer cells to block viral replication
to amplify the inflammatory process
Cytotoxic T cells ________. function mainly to stimulate the proliferation of other T cell populations can directly attack and kill other cells of the body require the double recognition signal of class I MHC plus class II MHC on the target cell in order to function self-destruct once the antigen has been neutralized
can directly attack and kill other cells of the body
Natural killer (NK) cells ________. are a type of phagocyte are also called cytotoxic T cells can kill cancer cells before the adaptive immune system is activated are cells of the adaptive immune system
can kill cancer cells before the adaptive immune system is activated
If a virus attacks a cell, which type of immunity would be activated? cell-mediated immunity (cellular immunity) humoral immunity antibody-mediated immunity
cell-mediated immunity (cellular immunity)
Which class of MHC proteins presents exogenous antigens? class I MHC proteins class II MHC proteins
class II MHC proteins
Which antimicrobial protein triggers inflammation? complement interferon pyrogen
complement
Which mechanism(s) of antibody action triggers the response of a plasma protein that will result in a membrane attack complex? complement activation neutralization precipitation agglutination
complement activation
Which of the innate defense mechanisms can lyse bacteria and mark cells for phagocytosis? natural killer (NK) cells interferons complement proteins cytokines
complement proteins
Antibody functions include all of the following EXCEPT ________. linking soluble antigens together so that they fall out of solution binding and inactivating chemical toxins released by bacteria or other microorganisms targeting foreign cells so that complement proteins can cause cellular lysis cross-linking cell-bound antigens on red blood cells when blood types are properly matched
cross-linking cell-bound antigens on red blood cells when blood types are properly matched
Activated T cells and macrophages release ________ to mobilize immune cells and attract other leukocytes into the area. cytokines interleukin 2 proteins perforins interleukin 1 proteins
cytokines
What type of T cell can directly attack and kill other cells, such as virus-infected cells? cytotoxic T (TC) cells APCs regulatory T (TReg) cells helper T (TH) cells
cytotoxic T (TC) cells
Activated CD8 T cells become __________. cytotoxic T cells B cells NK cells helper T cells
cytotoxic T cells
Which of the following cells engulf antigens by phagocytosis and present fragments of them on their own surfaces for recognition? T lymphocytes NK cells plasma cells dendritic cells
dendritic cells
What characterizes flattening of neutrophils to squeeze between the endothelial cells of the capillary walls? diapedesis margination chemotaxis leukocytosis
diapedesis
Which of the following phases involves white blood cells leaving capillaries? leukocytosis chemotaxis margination diapedesis
diapedesis
When do neutrophils enter the blood from the red bone marrow in response to leukocytosis-inducing factors? during chemotaxis during diapedesis during leukocytosis during margination
during leukocytosis
Four (or five) cardinal signs indicate inflammation. What specific sign of inflammation is the result of exudate in the tissue spaces? pain impaired function heat edema (swelling)
edema (swelling)
B cells must accomplish double recognition: they must simultaneously recognize self and nonself to be activated.
false
Discharge is one of the cardinal signs of inflammation.
false
In a case of immediate hypersensitivity, the immune system responds with an allergic response on the first exposure to the allergen.
false
Subacute hypersensitivities are categorically less harmful than acute (immediate) hypersensitivities.
false
Unless they are attached to protein carriers, haptens have immunogenicity but not reactivity.
false
Viral infection will provoke cell mediated immunity but will not activate a humoral response.
false
T helper cells ________. release B7 proteins often function to decrease the immune response bind tightly to target cells and release a lymphotoxin called perforin function in the adaptive immune system activation
function in the adaptive immune system activation
Which of the following describes a hapten? A hapten is a compound secreted by immunocompetent lymphocytes to demonstrate self-tolerance. A hapten is displayed on surface membranes of cells to be destroyed by the immune system. A hapten is a foreign molecule that triggers an immune response upon contact with mucous membranes. A hapten is a foreign molecule that becomes immunogenic when combined with body proteins.
hapten is a foreign molecule that becomes immunogenic when combined with body proteins.
Small molecules that bind with self-proteins to produce antigenic substances are called ________. reagins antibodies haptens ions
haptens
The primary immune response ________. .occurs when memory cells are stimulated is another name for immunological memory occurs more rapidly and is stronger than the secondary response has a lag period while B cells proliferate and differentiate into plasma cells
has a lag period while B cells proliferate and differentiate into plasma cells
Which lymphocytes act as the bridge between the cellular and humoral responses? helper T cells B cells regulatory T cells cytotoxic T cells
helper T cells
Which of the following are NOT appropriately matched? B cells: produce antibodies macrophages: antigen-presenting cells helper T cells: destroy infected body cells cytotoxic T cells: destroy virally infected cells
helper T cells: destroy infected body cells
Which of the following inflammatory chemicals is/are released by mast cells? histamine kinins complement prostaglandins
histamine
What type of immunity can be transferred by bodily fluids from one person to another, thus conferring immunity to the recipient? cellular immunity cell-mediated immunity humoral immunity
humoral immunity
Which of the following are NOT correctly matched? AIDS (acquired immune deficiency syndrome): helper T cells are destroyed by a virus immediate hypersensitivity: allergic contact dermatitis multiple sclerosis: autoimmune disorder severe combined immunodeficiency syndrome (SCID): genetic defect resulting in a shortage of B and/or T cells
immediate hypersensitivity: allergic contact dermatitis
Where does most exogenous antigen presentation take place? in lymphoid tissues and organs in the thymus in the bone marrow in blood plasma
in lymphoid tissues and organs
Phagocytotic cells such as macrophages identify a variety of enemies by recognizing markers unique to pathogens. They would be classified as which type of defense system? innate internal defenses innate external defenses adaptive defenses
innate internal defenses
Interferons ________. .are routinely used in nasal sprays for the common cold act by increasing the rate of cell division interfere with viral replication within cells are virus-specific, so that an interferon produced against one virus could not protect cells against another virus
interfere with viral replication within cells
What protein can be released by infected cells to help protect cells that have not yet been infected? interferon opsonins pyrogens complement
interferon
Which of the following innate internal defenses work by interfering with viral replication? complement proteins T lymphocytes interferons phagocytes
interferons
Immunocompetence ________. prevents intercellular communication so that only specific cell types respond to the invader requires exposure to an antigen is the ability of individual cells to recognize a specific antigen by binding to it occurs in one specific organ of the adaptive immune system
is the ability of individual cells to recognize a specific antigen by binding to it
An advantage to adaptive immunity is ________. its need for several cells to be activated over several days on first exposure the ability of its individual cells to respond to many different pathogens its memory cells that provide quicker, larger and more efficient immune response upon second and subsequent exposure to an antigen the use of antibodies that cause cell lysis and kill invading cells
its memory cells that provide quicker, larger and more efficient immune response upon second and subsequent exposure to an antigen
Anaphylactic shock is a rare but severe allergic response that may occur if the allergen enters the blood stream.
true
Fever is thought to be a beneficial response because it makes iron and zinc less available to support bacterial growth.
true
Perforins form complexes that penetrate the cell membrane and allow the passage of the apoptosis inducing protein granzyme to enter the targeted cell.
true
Soluble proteins secreted by plasma cells are called antibodies.
true
The directional movement of cells in response to chemicals is called chemotaxis.
true
irus-infected cells secrete interferons to "warn" other cells of the presence of virus and these other cells to inhibit viral replication.
true
Which of the following best illustrates artificially acquired active humoral immunity? vaccines antivenoms infection antibodies received in breast milk
vaccines
Which of the following is NOT one of the effects produced by the release of inflammatory chemicals? attraction of neutrophils redness vasoconstriction increased access of clotting chemicals
vasoconstriction
The redness and heat of an inflamed area are due to a local hyperemia caused by ________. phagocyte mobilization vasodilation complement production vasoconstriction
vasodilation
Which class of tissue graft is the LEAST likely to be accepted by a patient's body? xenograft isograft allograft autograft
xenograft
What type of immune system cell performs the most phagocytosis in the body? macrophages B lymphocytes. natural killer, or NK, cells neutrophils
macrophages
Regulatory T cells ________. .may function in preventing autoimmune reactions aid B cells in antibody production decrease their activity as antigenic stimulus decreases release cytokines that increase the activity of cytotoxic T cells and activated B cel
.may function in preventing autoimmune reactions
Innate immune system defenses include ________. .phagocytosis B cells T cells plasma cells
.phagocytosis
Phagocyte mobilization involves ________. diapedesis, during which cells line up against the capillary wall mainly neutrophil and macrophage migration into inflamed areas monocytes as the most active phagocyte margination, which is the process of white cell movement through the walls of capillaries into injured tissues
mainly neutrophil and macrophage migration into inflamed area
Which cells secrete histamines that trigger inflammatory pathways? neutrophils mast cells NK cells macrophages
mast cells
Place the following steps of phagocytosis in the order that they occur: Endosome fuses with lysozome Dendritic cell engulfs Rhinovirus Epitopes are attached to MHC-II Digestion of the Rhinovirus MHC-II plus the attached epitope move to the outside of the dendritic cell 2,1,3,4,5 1,2,4,3,5 2,1,4,3,5 2,4,1,3,5
2,1,4,3,5
Place the following steps of phagocytosis in the order that they occur: Endosome fuses with lysozome Dendritic cell engulfs Rhinovirus Epitopes are attached to MHC-II Digestion of the Rhinovirus MHC-II plus the attached epitope move to the outside of the dendritic cell 2,1,4,3,5 2,1,3,4,5 2,4,1,3,5 1,2,4,3,5
2,1,4,3,5
Correctly order the steps involved cellular immunity: The Tc recognizes the infected host cell The Tc interacts with epitope presented by MHC-I on the dendritic cell The Tc secretes perforin and granzyme, causing apoptosis The helper T cell activates the Tc cell 4,2,1,3 1,2,4,3 2,1,3,4 2,4,1,3
2,4,1,3
Correctly order the steps involved cellular immunity: The Tc recognizes the infected host cell The Tc interacts with epitope presented by MHC-I on the dendritic cell The Tc secretes perforin and granzyme, causing apoptosis The helper T cell activates the Tc cell 4,2,1,3 2,1,3,4 1,2,4,3 2,4,1,3
2,4,1,3
Which of the following statements regarding the primary versus the secondary immune response is true? A primary response results when naïve lymphocytes are activated, while a secondary response is a result of activating memory cells. A primary response leads to higher levels of antibodies than does a secondary response. A primary response occurs faster than a secondary response. The antibodies produced in a primary response bind to antigens more efficiently than the antibodies produced in a secondary immune response.
A primary response results when naïve lymphocytes are activated, while a secondary response is a result of activating memory cells.
Which of the following would be a component of the body's first line of defense? mucous membranes natural killer cells inflammation phagocytes
mucous membranes
A cellular component of the innate defenses includes ________. T cells plasma cells B cells natural killer cells
natural killer cells
Cancer cells and virus-infected body cells can be killed before activation of adaptive immunity by ________. pinocytosis natural killer cells T lymphocytes B lymphocytes
natural killer cells
Which of the following is NOT a step that ultimately leads to antibody production? Activation of cytotoxic T cells by helper T cells Differentiation of plasma cells Naive B cells conducting surveillance for foreign epitopes Activation of helper T cells by dendritic cel
Activation of cytotoxic T cells by helper T cells
Which of the following is NOT a step that ultimately leads to antibody production? Differentiation of plasma cells Activation of cytotoxic T cells by helper T cells Activation of helper T cells by dendritic cells Naive B cells conducting surveillance for foreign epitopes
Activation of cytotoxic T cells by helper T cells
Select the correct statement about active and passive immunity. The antibodies utilized in active immunity are acquired from another organism. Immunological memory is established by passive immunization. A vaccination is an example of the introduction of passive immunity into the body. Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies.
Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies.
Which of the following statements is true? Memory B cells are typically established when the B cell binds to an antigen. Adaptive defenses include humoral immunity only. Adaptive defenses include both humoral and cellular immunity. Innate defenses are enough to keep a person healthly.
Adaptive defenses include both humoral and cellular immunity
Which of the following statements is true? Adaptive defenses include humoral immunity only. Innate defenses are enough to keep a person healthly. Adaptive defenses include both humoral and cellular immunity. Memory B cells are typically established when the B cell binds to an antigen.
Adaptive defenses include both humoral and cellular immunity.
Which of the following occurs when antibodies block specific sites on viruses or bacterial exotoxins? neutralization agglutination precipitation complement fixation and activation
neutralization
Which of the following statements is a false or incorrect statement? It is our genes, not antigens, that determine what specific foreign substances our immune system will be able to recognize and resist. The lymphoid organs where lymphocytes become immunocompetent are called primary lymph organs. All other lymphoid organs are referred to as secondary lymphoid organs. After becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur. T cells and B cells become activated when they bind with recognized antigens.
After becoming immunocompetent, the naive T cells and B cells are exported to the bone marrow where the encounters with antigens occur.
What is meant by the clonal expansion of a B cell? An activated B cell will immediately begin to produce antibodies. An activated B cell divides into cells that give rise to memory B cells and plasma cells. An activated B cell will engulf and digest anything foreign. An activated B cell will kill infected host cells.
An activated B cell divides into cells that give rise to memory B cells and plasma cells.
What is meant by the clonal expansion of a B cell? An activated B cell will immediately begin to produce antibodies. An activated B cell will engulf and digest anything foreign. An activated B cell will kill infected host cells. An activated B cell divides into cells that give rise to memory B cells and plasma cells.
An activated B cell divides into cells that give rise to memory B cells and plasma cells.
Phagocytes are unable to adhere to bacteria that have external capsules concealing their membrane carbohydrates. Our immune system gets around this problem by coating such pathogens with __________. phagosomes toll-like receptors opsonins mucin
opsonins
Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed ________. chemotaxis diapedesis opsonization agglutination
opsonization
Which of the following is an effect of complement activation? fever tissue repair T cell activation opsonization
opsonization
The antivenom used to treat a venomous snake bite is an antibody produced in an animal such as a horse. Suppose these antibodies are injected into a patient who has been bitten by a venomous snake. How would you classify the resulting humoral immunity? active immunity, artificially acquired passive immunity, artificially acquired active immunity, naturally acquired passive immunity, naturally acquired
passive immunity, artificially acquired
Which of these mechanisms do cytotoxic T (TC) cells use to destroy a target--that is, to deliver a lethal hit? agglutination of target cells producing antibodies perforation of the membrane opsonization
perforation of the membrane
What cells make antibodies? cytotoxic T cells memory T cells memory B cells plasma B cells
plasma B cells
Which of the following is NOT a role of activated complement? prevention of immediate hypersensitivity reactions insertion of MAC and cell lysis enhancement of inflammation opsonization
prevention of immediate hypersensitivity reactions
Fever ________. decreases the metabolic rate of the body to conserve energy causes the liver to release large amounts of iron, which seems to inhibit bacterial replication is a higher-than-normal body temperature that is always dangerous production is regulated by chemicals that reset the body's thermostat to a higher setting
production is regulated by chemicals that reset the body's thermostat to a higher setting
Which of the following examples below describes an autoimmune disease? Antibody binding to acetylcholine receptors of the motor end plate resulting in muscle weakness. Release of bacterial endotoxins that block acetylcholine release result in muscle paralysis .Uncontrolled cell division resulting in cell surface abnormalities recognized by NK cells. Infection and death of T helper cells by a virus, resulting in a loss of adaptive immunity.
Antibody binding to acetylcholine receptors of the motor end plate resulting in muscle weakness.
Which of the following is true of antigens? Antigens are substances that activate the adaptive immune response. Antigens are typically composed of nucleotides. Antigens are produced by the body in response to a foreign invader. Antigens are limited to one antigenic determinant per antigen molecule.
Antigens are substances that activate the adaptive immune response.
Which of the statements below does NOT describe antigens? The parts of antigen molecules that initiate immune responses are called epitopes or antigenic determinants. Antigens exhibit immunogenicity and reactivity. Antigens can include proteins, nucleic acids, lipoproteins, glycoproteins, and certain large polysaccharides. Antigens only come from microbes.
Antigens only come from microbes.
A class I MHC protein presents an antigen. What type of cell is likely presenting and to what type of cell would it be presented? An antigen-presenting cell (APC) would present antigens to a CD8 cell. Any nucleated cell would present antigens to a CD8 cell. Any nucleated cell would present antigens to a CD4 cell. An antigen-presenting cell (APC) would be presented to a CD4 cell.
Any nucleated cell would present antigens to a CD8 cell.
What is the role of interferon in defense against disease? ]activates the complement mechanism protects cells that have not yet been infected by viruses protects cells that have not yet been infected by bacteria activates the inflammatory process
protects cells that have not yet been infected by viruses
During inflammation, fluids will passively diffuse out of blood vessels into the nearby infected tissues. This implies all of the following EXCEPT ________. nearby capillaries have become more permeable the surrounding tissue will swell with excessive fluids B-lymphocytes will differentiate to become plasma cells the increased volume in the infected tissue contributes to pain
B-lymphocytes will differentiate to become plasma cells
Which pair of molecules do NOT directly interact with one another? BCR and TCR CD4 and MHC-II BCR and epitope CD8 and MHC-I
BCR and TCR
Which pair of molecules do NOT directly interact with one another? CD4 and MHC-II BCR and TCR BCR and epitope CD8 and MHC-I
BCR and TCR
