Ch. 16 and 17 Mastering Micro.

What is the correct sequence of events for activation of a B cell by a T-dependent antigen?

(1) Immunoglobulin receptors on the B cell recognize and bind the antigen. (2) An antigen fragment in complex with MHC class 2 is displayed on the B cell's surface. (3) The MHC-antigen complex binds a receptor on a TH cell. (4) The TH cell secretes cytokines that activate the B cell.

At a minimum, the human immune system is capable of recognizing approximately how many different antigens?

10^15

TLRs attach to all of the following EXCEPT

AMPs.

Which of the following statements concerning phagocytosis is true?

Bacteria are digested when the phagosome fuses with a lysosome.

Which of the following statements concerning cellular immunity is FALSE?

Cellular immunity involves cells that recognize antigens and make specific antibodies against them.

An example of a TLR would be peptidoglycan found in the cell wall of gram-positive bacteria.

False

Digestion of microorganisms occurs in phagosomes.

False

Memory cells do not require B cell receptors.

False

Plasma cells will eventually differentiate into memory cells.

False

The dermis is composed of connective tissue and serves the primary purpose of providing direct protection from the external environment.

False

The inflammatory response can only be triggered by an infection.

False

All of the following protect the skin and mucous membranes from infection EXCEPT

HCl

The antibodies found in mucus, saliva, and tears are

IgA

The antibodies found almost entirely and only on the surface of B cells (not secreted from them), and which always exist as monomers, are

IgD

The antibodies that can bind to large parasites are

IgE

The most abundant class of antibodies in serum is

IgG

In addition to IgG, the antibodies that can fix complement are

IgM

Large antibodies that agglutinate antigens are

IgM

Which of the following statements about innate immunity is true?

Innate immunity is present at birth.

__________ is/are always present in an individual's blood. However, in the absence of infection, it is in an inactive form.

Kinins

The following events elicit an antibody response. What is the third step?

TH cell recognizes antigen-digest and MHC II.

Which of the following statements is FALSE?

The constant region of a heavy chain is the same for all antibodies.

Which of the following is NOT a characteristic of B cells?

They recognize antigens associated with MHC I.

Aspirin alleviates pain, inflammation, and fever by inhibiting prostaglandins.

True

Histamine and kinins cause increased blood flow and capillary permeability.

True

The implementation of vaccinations occurred prior to experimental support for the germ theory of disease.

True

In the figure, which areas represent antigen-binding sites?

a and b

Which of the following is the best definition of antigen?

a chemical that elicits an antibody response and can combine with these antibodies

All of the following pertain to fever EXCEPT that it

accelerates microbial growth by increasing iron absorption from the digestive tract.

Margination refers to

adherence of phagocytes to the lining of blood vessels.

All of the following are components of the inflammatory process EXCEPT

antibody synthesis

Plasma cells are activated by a(n)

antigen

What type of immunity results from vaccination?

artificially acquired active immunity

What type of immunity results from transfer of antibodies from one individual to a susceptible individual by means of injection?

artificially acquired passive immunity

A chill is a sign that

body temperature is rising.

In the figure, which letter on the graph indicates the patient's secondary response to a repeated exposure with the identical antigen?

c

In the figure, which areas are similar for all IgG antibodies?

c and d

Which of the following bacterial components would most likely result in B cell stimulation by T-independent antigens?

capsule

Lysozyme and the antibiotic penicillin have similar mechanisms of action in that they both cause damage to the bacterial

cell wall

Which of the following is mismatched?

chemotaxis chemical degradation inside a phagolysosome

Which of the following statements is NOT a possible outcome of antigen-antibody reaction?

clonal deletion

After ingesting a pathogen, lysosomal enzymes produce all of the following EXCEPT

complement

You note that the body temperature of one of your patients is starting to increase. As a result, you can infer that all of the following may be occurring in this patient EXCEPT __________.

dilation of blood vessels

In the figure, which letter on the graph indicates the highest antibody titer during the patient's response to a second and distinct/different antigen?

e

All of the following are effects of histamine EXCEPT

fever

Each of the following provides protection from phagocytic digestion EXCEPT

formation of phagolysosomes.

The swelling associated with inflammation decreases when the fluid

goes into lymph capillaries.

Which of the following is an effect of opsonization?

increased adherence of phagocytes to microorganisms

Innate immunity

is nonspecific and present at birth.

All of the following increase blood vessel permeability EXCEPT

lysozyme

Phagocytes utilize all of the following to optimize interaction with (getting to and getting hold of) microorganisms EXCEPT

lysozyme

Which non-specific defense mechanism is mismatched with its associated body structure or body fluid?

mucociliary escalator intestines

An individual may be exposed to a pathogen and become infected without actually getting sick. This is known as a subclinical infection. Even in subclinical infections, the individual's adaptive immune system can generate memory for the pathogen. What type of adaptive immunity is this?

naturally acquired active immunity

What type of immunity results from recovery from mumps?

naturally acquired active immunity

Newborns' immunity due to the transfer of antibodies across the placenta is an example of

naturally acquired passive immunity.

When an antibody binds to a toxin, the resulting action is referred to as

neutralization

A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes?

phagocytosis in the inflammatory response

Neutrophils with defective lysosomes are unable to

produce toxic oxygen products.

All of the following are effects of histamine EXCEPT

production of antibodies.

Innate immunity includes all of the following EXCEPT

production of antibody.

Which of the following is the best definition of epitope?

specific regions on antigens that interact with antibodies

In the figure, the arrow at time (c) indicates

the secondary response

The specificity of an antibody is due to

the variable portions of the H and L chains.

The function of the "ciliary escalator" is to

trap inhaled dust and microorganisms in mucus and propel it away from the lower respiratory tract.

All of the following occur during inflammation. What is the first step?

vasodilation