Question 1

What affect does the process of histamine binding to the histamine-2 (H₂)receptor have on inflammation?

Accepted Answer

Binding of histamine to the H₁ receptor is essentially proinflammatory; that is,it promotes inflammation.On the other hand,binding histamine to the H₂ receptor is generally antiinflammatory because it results in the suppression of leukocyte function.The other options do not accurately describe the affect histamine binding to the H₂ receptor has on inflammation.

Question 2

Which chemical interacts among all plasma protein systems by degrading blood clots,activating complement,and activating the Hageman factor?

Accepted Answer

Only plasmin regulates clot formation by degrading fibrin and fibrinogen,and it can activate the complement cascade through components C1,C3,and C5.Plasmin can activate the plasma kinin cascade by activating the Hageman factor (factor XII)and producing prekallikrein activator.

Question 3

The function of opsonization related to the complement cascade is to:

Accepted Answer

C3b adheres to the surface of a pathogenic microorganism and serves as an efficient opsonin.Opsonins are molecules that tag microorganisms for destruction by cells of the inflammatory system,primarily neutrophils and macrophages.The other options do not accurately describe the function of opsonization related to the complement cascade.

Question 4

Which chemical mediator derived from mast cells retracts endothelial cells to increase vascular permeability and to cause leukocyte adhesion to endothelial cells?

Accepted Answer

The biologic activity of platelet-activating factor is virtually identical to that of leukotrienes; namely,it causes endothelial cell retraction to increase vascular permeability,leukocyte adhesion to endothelial cells,and platelet activation.The other options do not accurately identify the chemical mediator derived from the process described in the question.

Question 5

Some older adults have impaired inflammation and wound healing because of which problem?

Accepted Answer

In some cases,impaired healing is not directly associated with aging,in general,but can instead be linked to a chronic illness such as cardiovascular disease or diabetes mellitus.The other problems are not related to the aging process.

Question 6

What is an outcome of the complement cascade?

Accepted Answer

The complement cascade can be activated by at least three different means,and its products have four functions: (1)anaphylatoxic activity,resulting in mast cell degranulation,(2)leukocyte chemotaxis,(3)opsonization,and (4)cell lysis.The other options do not accurately describe an outcome of the complement cascade.

Question 7

Which bacterium grows in the intestines after prolonged antibiotic therapy?

Accepted Answer

Prolonged antibiotic treatment can alter the normal intestinal flora,decreasing its protective activity and leading to the overgrowth of other microorganisms,such as the yeast C.albicans or the bacterium C.difficile.The other options do not accurately identify intestinal bacterium whose growth is a result of prolonged antibiotic therapy.

Question 8

Frequently when H₁ and H₂ receptors are located on the same cells,they act in what fashion?

Accepted Answer

Both types of receptors are distributed among many different cells and are often present on the same cells and may act in an antagonistic fashion.For instance,neutrophils express both types of receptors,with stimulation of H₁ receptors resulting in the augmentation of neutrophil chemotaxis and H₂ stimulation resulting in its inhibition.The other options do not accurately describe the relationship between H₁ and H₂ receptors.

Question 9

Activation of the classical pathway begins with:

Accepted Answer

Activation of the classical pathway begins only with the activation of protein C1 and is preceded by the formation of a complex between an antigen and an antibody to form an antigen-antibody complex (immune complex)

Question 10

What process causes heat and redness to occur during the inflammatory process?

Accepted Answer

The increased blood flow as a result of vasodilation and increasing concentration of red cells at the site of inflammation cause locally increased warmth and redness.The other options do not accurately identify the process that results in inflammatory redness and heat.

Question 11

What plasma protein system forms a fibrinous meshwork at an inflamed site?

Accepted Answer

The coagulation (clotting)system is a group of plasma proteins that form a fibrinous meshwork at an injured or inflamed site.This protein system (1)prevents the spread of infection to adjacent tissues,(2)traps microorganisms and foreign bodies at the site of inflammation for removal by infiltrating cells (e.g.,neutrophils and macrophages),(3)forms a clot that stops the bleeding,and (4)provides a framework for future repair and healing.The other options do not accurately identify such a protein system.

Question 12

In the coagulation (clotting)cascade,the intrinsic and the extrinsic pathways converge at which factor?

Accepted Answer

The coagulation cascade consists of the extrinsic and intrinsic pathways that converge only at factor X.

Question 13

What causes the edema that occurs during the inflammatory process?

Accepted Answer

The increased flow and capillary permeability result in a leakage of plasma from the vessels,causing swelling (edema)in the surrounding tissue and is solely responsible for inflammation-induced edema.

Question 14

Which action is a purpose of the inflammatory process?

Accepted Answer

If the epithelial barrier is damaged,then a highly efficient local and systemic response (inflammation)is mobilized to limit the extent of damage,to protect against infection,and to initiate the repair of damaged tissue.The other options do not accurately identify a purpose of the inflammatory process.

Question 15

What is the inflammatory effect of nitric oxide (NO)?

Accepted Answer

Effects of NO on inflammation include vasodilation by inducing relaxation of vascular smooth muscle,a response that is local and short lived,and by suppressing mast cell function,as well as platelet adhesion and aggregation.The other options do not accurately identify the effect of NO on the process of inflammation.

Question 16

The chemotactic factor affects the inflammatory process by:

Accepted Answer

Two chemotactic factors,neutrophil chemotactic factor (NCF)and eosinophil chemotactic factor of anaphylaxis (ECF-A),are released during mast cell degranulation.NCF attracts neutrophils (a type of leukocytes),and ECF-A attracts eosinophils to the site of inflammation.The other options do not accurately describe the affect chemotactic factors have on the inflammatory process.

Question 17

Which component of the plasma protein system tags pathogenic microorganisms for destruction by neutrophils and macrophages?

Accepted Answer

C3b (a component of the complement cascade)adheres to the surface of a pathogenic microorganism and serves as an efficient opsonin.Opsonins are molecules that tag microorganisms for destruction by cells of the inflammatory system,primarily neutrophils and macrophages.The other options do not accurately identify a component capable of tagging pathogenic microorganisms.

Question 18

How do surfactant proteins A through D provide innate resistance?

Accepted Answer

The lung produces and secretes a family of glycoproteins,collectins,which includes surfactant proteins A through D and mannose-binding lectin.Collectin binding facilitates macrophages to recognize the microorganism,enhancing macrophage attachment,phagocytosis,and killing.The other options do not accurately identify how surfactant proteins provide innate resistance.

Question 19

What is the vascular effect of histamine released from mast cells?

Accepted Answer

C2b affects smooth muscle,causing vasodilation and increased vascular permeability.C3a,C5a,and,to a limited extent,C4a are anaphylatoxins; that is,they induce rapid mast cell degranulation (i.e.,release of granular contents)and the release of histamine,causing vasodilation and increased capillary permeability.The other options do not accurately describe the vascular effect of histamine released from mast cells?

Question 20

Which secretion is a first line of defense against pathogen invasion that involves antibacterial and antifungal fatty acids,as well as lactic acid?

Accepted Answer

Sebaceous glands in the skin secrete sebum that is made up of antibacterial and antifungal fatty acids and lactic acid that provide the first-line barrier against pathogen invasion.

Quiz 7: Innate Immunity: Inflammation

What affect does the process of histamine binding to the histamine-2 (H₂) receptor have on inflammation?