Chapter 15

Antibody response

B cells

Plasma cells are effector ______ that produce _______. B cells; ribozymes T cells; antibodies T cells; ribozymes B cells; antibodies

B cells; antibodies

An initial adaptive immune response can be produced and protecting an individual from an infection in 24 hours. True - Think about all the things that must take place to get an adaptive response to a protective level. Can all of that happen in 24 hours? False

False

IgM is the main circulating antibody in the bloodstream. True - Reason: It only accounts for about 5-13% of circulating antibody at a given time. False

False

Humoral immunity is mediated by five classes of immunoglobulins:

IgA IgD IgE IgG IgM

Which immunoglobulin is barely detectable in serum because it is generally tightly bound via the Fc region to basophils and mast cells? IgE IgM IgD IgA IgG

IgE

The human immune system produces five main classes of antibodies. What are they? Multiple select question. IgG IgD IgC IgM IgA IgE IgT IgP

IgG IgD IgM IgA IgE

All of the following are usually true of a secondary response EXCEPT ______. Multiple choice question. memory cells are already in place from the previous exposure to the same antigen class switching has already occurred IgG is the main antibody used affinity maturation has already occurred IgM is the first antibody produced

IgM is the first antibody produced

which include B cells and T cells, are the primary cell type involved in the adaptive immune responses.

Lymphocytes

______ cells are responsible for the effectiveness of the secondary response. Multiple choice question. Memory correct Plasma Secondary

Memory

__________________ B cells are long-lived and allow for a much faster response if the same antigen is encountered at a later date.

Memory

Interact with target cells and then cause changes in those cells

T cells

During an initial or primary exposure to an antigen, adaptive immunity generally takes about ______ to build. a month an hour a week a day

a week

The cytokines released by helper T cells (TH cells) help to coordinate, activate, and support ______. a. B cells b. nerve cells Reason: These cells aren't involved in immune responses. c. cytotoxic T cells d. endothelial cells Reason: Cytokines can have an effect on these cells, but the cytokines involved don't come from helper T cells. e. macrophages

a. B cells c. cytotoxic T cells e. macrophages

An antigen is a molecule capable of interacting with ______. Multiple select question. a. an antibody molecule b. an antibody receptor on a macrophage Reason: This receptor would bind antibody, not antigen. c. a B-cell receptor d. a complement receptor on a macrophage Reason: This receptor would bind complement, not antigen.

a. an antibody molecule c. a B-cell receptor

Secretory IgA (sIgA), the dimer form of IgA, can be found in ______. Multiple select question. a. breast milk b. blood - Reason: That would be the monomeric form of IgA, not the dimeric secreted form. c. saliva d. tears

a. breast milk c. saliva d. tears

ecretory IgA is important in mucosal immunity and can be found in the mucosal membranes of the ______. Multiple select question. a. gastrointestinal tract b. respiratory tract c. blood vessels Reason: The blood vessels have an endothelial lining, not a mucous membrane. d. skin Reason: The skin has a layer of keratinized skin cells on its surface, not a mucous membrane. e. genitourinary tract

a. gastrointestinal tract b. respiratory tract e. genitourinary tract

The primary cellular participants in the adaptive immune responses are Multiple choice question. a. lymphocytes b. antibodies Reason: What is the cell that produces these? c. macrophages Reason: Macrophages are generally involved in innate immunity. d. neutrophils Reason: Neutrophils are a 'first responder' cell type of the innate immune system. e. complement proteins Reason: Complement proteins are involved in innate immune responses.

a. lymphocytes

When an antigen is encountered for a second time later in life, there is a ______ antigen-specific immune response called the ______ response. a. stronger; secondary b. secondary; adaptive Reason: The antigen-specific responses are all adaptive. Also, they don't occur secondary to some process in the second exposure. c. weaker; secondary Reason: Why would there be an adaptation for a weaker response upon repeated exposure? d. memory; primary Reason: The original memory from the primary response would be invoked here in the secondary response.

a. stronger; secondary

Neutralization prevents ______. Multiple choice question. a. viruses and toxins from attaching to target cells and damaging them b. macrophages from ingesting viruses or toxin particles Reason: Neutralization may indirectly increase the efficiency of phagocytosis. c. antibodies from binding to virus or toxin particles Reason: This is actually the definition of neutralization. d. neutrophils from recognizing antigen molecules Reason: Why would we want to prevent the protective effects of neutrophils? However, they're not involved in neutralization.

a. viruses and toxins from attaching to target cells and damaging them

Humoral immunity is generally used to eliminate extracellular antigens such as ______. Multiple select question. a. viruses in tissue fluids b. bacteria c. viruses replicating in cells Reason: Viruses inside of cells generally can't be attached or attacked by humoral immunity components. d. toxins e. tuberculosis pathogens ingested by macrophages Reason: The bacterium that causes tuberculosis generally can't be attacked by humoral immune responses when it's inside its host macrophage cell.

a. viruses in tissue fluids b. bacteria d. toxins

The memory response of adaptive immunity ______. Multiple choice question. a. yields a stronger response upon repeated exposures with the same antigens b. acts with the same speed upon repeated exposures with the same antigens Reason: Think of what the term "adaptive" means. Will it respond the same way that it did the first time around? c. provides the same degree of response upon repeated exposures with the same antigens Reason: Think of what the term "adaptive" means. Will it respond the same way that it did the first time around?

a. yields a stronger response upon repeated exposures with the same antigens

The term "antigen" is derived from the descriptive expression " __________ generator."

antibody

The clonal selection theory describes how the body can make a seemingly unlimited range of ______. antibody specificities antibody classes

antibody specificities

The main function of the lymphatic system is to allow ________ to interact with and activate lymphocytes.

antigens

The lymphatic system's primary role is to _______. Multiple choice question. a. bring antigens into contact with complement proteins for effective binding, followed by elimination Reason: This would be an innate immune response. The lymphatic system is involved in adaptive immunity. b. bring antigens into contact with lymphocytes, allowing activation, proliferation, and differentiation of specific B and T cells into effector cells c. provide a safe environment in which B cells and T cells can mature Reason: B cells mature in the bone marrow, and T cells mature in the thymus.

b. bring antigens into contact with lymphocytes, allowing activation, proliferation, and differentiation of specific B and T cells into effector cells

The term opsonization refers to ______. Multiple choice question. a. binding of toxin molecules with antibodies, preventing them from attaching to and affecting host cells Reason: This would be more of a direct protective effect of antibodies binding to antigens. b. coating a bacterial cell with antibodies, so that the "red flag" regions alert other components of the immune system c. binding of viral particles with antibodies, preventing them from attaching to and infecting host cells Reason: This would be more of a direct protective effect of antibodies binding to antigens. d. coating a bacterial cell with antibodies, so that the antigen-binding regions of the antibodies are available for binding by our immune system cells Reason: Which part of the antibodies binds to the antigens again? And which part us exposed for our own cells to bind?

b. coating a bacterial cell with antibodies, so that the "red flag" regions alert other components of the immune system

IgM ______. Multiple choice question. a. accounts for 80-85% of the circulating antibody levels Reason: This would be IgG antibodies, not IgM. b. is the first class of antibody produced during a primary response to an antigen c. is produced in higher quantities when an antigen is re-encountered Reason: Later responses are usually shifted away from IgM. d. is the second class of antibody produced during a primary response to an antigen Reason: IgM is the very first antibody type produced in a primary response.

b. is the first class of antibody produced during a primary response to an antigen

A secondary adaptive immune response ______. Multiple choice question. a. takes the same time to generate as the primary response - Reason: In the adaptive response, response time shortens after the first exposure due to reactivation of the memory of the initial response. b. occurs when an antigen that has already been encountered is encountered again c. produces the same degree or strength as the primary response - Reason: In the adaptive response, repeated responses increase in strength against the antigen in question. d. occurs when an antigen similar to, yet different from, the original antigen is encountered Reason: Adaptive immune responses are highly specific, so even a related antigen wouldn't restimulate the memory of the response to the original antigen.

b. occurs when an antigen that has already been encountered is encountered again

When antigen is introduced, ______. a. most B cells multiply, generating a wide range of antibody molecules b. only the B cells capable of making the appropriate antibody can multiply

b. only the B cells capable of making the appropriate antibody can multiply

The primary adaptive immune response ______. Multiple choice question. a. is very fast, since it is the first time the pathogen is "seen" by the system Reason: Think about the term "adaptive" here--when something needs to "adapt" to a situation, does it do so incredibly quickly, or does it take some time? b. produces "memory" to be used later on in subsequent exposures c. will be identical in nature to the secondary response to the same antigen at a later date. Reason: Think about the term "adaptive" in this case. Why would it be the same upon repeated exposures to the same thing?

b. produces "memory" to be used later on in subsequent exposures

The main function of TH cells is ______. Multiple choice question. a. direct elimination of extracellular antigens Reason: TH cells might assist other cells in doing this, but they don't do it directly. b. production of cytokines that direct and support other immune system cells c. direct elimination of intracellular antigens Reason: TH cells might assist other cells in doing this, but they don't do it directly. d. secretion of antimicrobial proteins into the bloodstream Reason: The proteins released by helper T cells are generally not antimicrobial in their activity. They also are generally not secreted in high levels directly into the bloodstream.

b. production of cytokines that direct and support other immune system cells

What are the basic functions of helper T cells? Multiple select question. a. Induction of apoptosis in infected self cells Reason: Helper T cells don't perform this task--cytotoxic T cells do. b. Direct lysis of extracellular bacteria Reason: Helper T cells don't directly attack pathogens. c. Activation of B cells d. Coordination of activities of B cells, macrophages, and other T cells e. Activation of macrophages

c. Activation of B cells d. Coordination of activities of B cells, macrophages, and other T cells e. Activation of macrophages

Only a trace amount of IgE is detectable in the serum. Why is this? Multiple choice question. a. It is quickly excreted by the kidneys in urine, preventing it from ever building up to detectable levels. Reason: The kidneys are no better at excreting IgE than they would be for any of the classes of antibodies. b. It is not produced in large amounts, ever. Reason: IgE can be produced in large amounts. c. It is quickly bound by IgE receptors on basophils and mast cells, where it is used in allergic responses. d. It has a very short half-life, so it is degraded too quickly to build up to large levels. Reason: The half-life of IgE isn't this short.

c. It is quickly bound by IgE receptors on basophils and mast cells, where it is used in allergic responses.

Helper T cells orchestrate the immune response by ______. Multiple select question. a. producing antibodies b. directing cancerous or infected cells to undergo apoptosis c. activating B cells and macrophages d. directing the activities of B cells, macrophages, and T cells

c. activating B cells and macrophages d. directing the activities of B cells, macrophages, and T cells

Memory B cell production occurs ______. Multiple choice question. a. before affinity maturation has taken place Reason: This would leave behind a memory of a subpar response in place. b. only after all antigen has been eliminated Reason: Usually their production runs in parallel with the elimination of the antigen by the effector cells. c. after class switching has taken place d. before class switching has taken place Reason: This would leave behind the memory of a subpar response in place.

c. after class switching has taken place

The stem of the Y-shaped antibodies has a highly ______. Multiple choice question. a. variable amino acid sequence that provides the "red flag" for other immune system components to eliminate the antigen Reason: While the stem is the "red flag," it isn't highly variable in its amino acid composition. b. variable amino acid sequence that provides the basis for antibody specificity to antigens Reason: The stem region isn't involved in binding of the antibody to its antigen. Also, it isn't highly variable in its amino acid sequence. c. conserved amino acid sequence that provides the "red flag" for other immune system components to eliminate the antigen d. conserved amino acid sequence that provides the basis for antibody specificity to antigens Reason: The stem region isn't involved in binding of the antibody to its antigen.

c. conserved amino acid sequence that provides the "red flag" for other immune system components to eliminate the antigen

Penicillin is a hapten, meaning that it ______. normally acts as a strong immunogen has multiple repeating subunits that elicit a T-independent B-cell response can elicit an immune response once attached to a carrier protein

can elicit an immune response once attached to a carrier protein

The portion of antibody molecules that has a consistent amino acid sequence regardless of the epitope recognized is referred to as the _________ region.

constant or Fc

When a toxin or virus is neutralized, it is ______. Multiple choice question. a. destroyed by inducing apoptosis in the infected host cell Reason: B cells and antibodies don't induce apoptosis in virally infected cells. b. coated with complement proteins Reason: There is coating of the particles with something, but it isn't complement proteins. c. ingested by a phagocyte Reason: Neutralization may enhance phagocytosis, but this isn't the actual process of neutralization. d. coated with antibody molecules e. bound by T cells via their T cell receptors (TCRs) Reason: TCRs cannot bind whole, free antigens directly.

d. coated with antibody molecules

The amino acid sequence of the end of the "arms" of different antibody molecules is ______. Multiple choice question. a. conserved, thus providing the "red flag" for other immune system components to eliminate the antigen Reason: The "arms" of the Y-shaped molecule isn't the "red flag" for other immune system components. It is also not highly conserved in its amino acid sequence. b. conserved, thus providing the basis for antibody specificity to antigens Reason: If the sequence were highly conserved between all antibodies, how would we get different specificities? c. variable, thus providing the "red flag" for other immune system components to eliminate the antigen Reason: The "arms" of the Y-shaped molecules isn't the "red flag" for other immune system components. d. variable, thus providing the basis for antibody specificity to antigens

d. variable, thus providing the basis for antibody specificity to antigens

Cell-mediated immunity (CMI) deals with intracellular pathogens and antigens such as ______. Multiple choice question. a. viruses in tissue fluids Reason: Viruses in tissue fluids are outside of cells--the humoral systems deal with these more efficiently. b. toxin molecules Reason: Toxin molecules are eliminated more efficiently before they get into a cell in the first place. c. bacteria in the bloodstream Reason: Bacteria in the bloodstream itself (not inside of other cells) would probably be best attacked by complement proteins and/or antibodies. d. viruses replicating in a cell

d. viruses replicating in a cell

The process of antibody-____________ cellular cytotoxicity (ADCC) relies on IgG antibodies binding targets, allowing NK cells to bind to their exposed Fc regions.

dependent

Unlike B and T cells, NK cells ______. Multiple choice question. do not have antigen specific receptors are not innate lymphoid cells (ILCs) are not lymphocytes are not leukocyte

do not have antigen specific receptors

Distinct regions of the antigen that are recognized by the antibody are known as antigenic determinants or

epitopes

Humoral immunity is best at eliminating ______ antigens such as viruses in the bloodstream or tissue fluid, whereas cell-mediated immunity removes ______ antigens such as viruses within host cells. inert; active extracellular; intracellular correct non-living; living intracellular; extracellular

extracellular; intracellular

One of the traits of IgG molecules that gives them such a strong capacity for protective responses is their long ___________ -life of 21 days.

half

A(n) _______ is a small molecule that does not elicit an immune response unless complexed with a carrier protein. allergen antigen immunogen cytokine hapten

hapten

The cells that have the general role of interacting with target cells and then inducing changes in them are ______. helper T cells plasma B cells cytotoxic T cells

helper T cells cytotoxic T cells

Natural killer cells belong to the group of lymphocytes called ______. B lymphocytes innate lymphoid cells T lymphocytes

innate lymphoid cells

Cell- ___________ immunity deals with microbial invaders residing within a host cell, such as a virus replicating inside a cell, whereas __________ immunity deals with invaders in the bloodstream and tissue fluids.

mediated, humoral

Both B and T cells can form ___________ cells that react quickly if the same antigen is encountered at a later time.

memory

In the case of adaptive immunity, a successful first encounter with a pathogen leads to a faster and more effective reaction upon re-exposure. In essence, the immune system "learns" how to effectively protect against the pathogen. This phenomenon is called immunological

memory

The secondary response is much faster and more effective than the primary response because of the presence of _____________lymphocytes left over from the primary response.

memory

With respect to humoral immunity, the cells responsible for the efficiency of the secondary response are ______. memory T helper cells memory B cells memory T cytotoxic cells naive T helper cells plasma cells naive B cells naive T cytotoxic cells

memory B cells

Phagocytes have receptors for the Fc portion of certain classes of antibody molecules, making it easier for the phagocyte to engulf antibody-coated antigens. This mechanism that enhances phagocytosis is called

opsonization

An epitope is ______. too small to stimulate an immune response unless it is bound to a protein carrier the antigen binding site of an antibody molecule part of an antigen that stimulates production of and binds to specific antibody found only in IgG and IgM

part of an antigen that stimulates production of and binds to specific antibody

Differentiated B lymphocytes that produce antibodies are called ________ cells

plasma

The first adaptive immune response to a particular antigen is called the _________ response.

primary

If a person lost the ability to make memory B cells, then the secondary response would be nearly identical to the ______. Multiple choice question. primary cell-mediated response primary humoral response secondary humoral response secondary cell-mediated response

primary humoral response

When comparing two different antibody molecules that bind to different epitopes, the amino acid sequence in the _________ region of each molecule will be different.

variable