Which of the following provides a first line of defense against pathogens?
intact skin and mucous membranes
With what does our immune system coat pathogens to facilitate their capture and accelerate phagocytosis?
opsonins
Four (or five) cardinal signs indicate inflammation. What specific sign of inflammation is the result of exudate in the tissue spaces?
edema (swelling)
Which of the following inflammatory chemicals is/are released by mast cells?
histamine
What characterizes the chemotaxis phase of phagocyte mobilization?
Neutrophils and other WBCs migrate up the gradient of chemotactic agents to the site of injury.
What protein can be released by infected cells to help protect cells that have not yet been infected?
interferon
How do interferons protect against viral infection in healthy cells?
Interferons block viral reproduction in healthy cells through the production of antiviral proteins.
Which of the following phases involves white blood cells leaving capillaries?
diapedesis
Which of the following is an effect of complement activation?
opsonization
Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed ________.
opsonization
Innate immune system defenses include ________.
phagocytosis
Which of the following is not a complement activation pathway?
lactate pathway
What are the complement activation pathway?
lectin pathway
alternative pathway
classical pathway
The directional movement of cells in response to chemicals is called chemotaxis.
true
multiple sclerosis: autoimmune disorder
true
severe combined immunodeficiency syndrome (SCID): genetic defect resulting in a shortage of B and/or T cells
true
AIDS (acquired immune deficiency syndrome): helper T cells are destroyed by a virus
true
Allergic contact dermatitis is a delayed hypersensitivity response; it is not characterized by an immediate response.
true
What types of antigen do T cells NOT recognize?
self antigens
One antigen may have many different antigenic determinants and may therefore cause the formation of more than one antibody.
true
How does a lymphocyte exhibit immunocompetence?
by being able to recognize their one specific antigen
What describe the adaptive immune response?
It is systemic.
It is specific.
It has memory.
Which of the following cells engulf antigens and present fragments of them on their own surfaces for recognition?
dendritic cells
B lymphocytes develop immunocompetence in the ________.
bone marrow
The antivenom used to treat venomous snake bites 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?
passive immunity, artificially acquired
Which of the following best illustrates artificially acquired active humoral immunity?
vaccines
What part of the antibody’s structure determines its class?
constant (C) region
Which of the following occurs when antibodies block specific sites on viruses or bacterial exotoxins?
neutralization
Which mechanism(s) of antibody action result(s) in cell lysis?
complement fixation and activation
T cells achieve self-tolerance in the __________.
thymus
Which of the following are antigen-presenting cells (APC)?
B Cells
Which of the following statements regarding the primary versus the secondary immune response is true?
A primary response results when naive lymphocytes are activated, while a secondary response is a result of activating memory cells.
Vaccines provide what type of immunity?
artificial active
Which of the following are properly matched?
IgG: most abundant antibody
Which of the following is associated with passive immunity?
passage of IgG antibodies from a pregnant mother to her fetus
The primary immune response ________.
has a lag period while B cells proliferate and differentiate into plasma cells
Soluble proteins secreted by plasma cells are called antibodies.
true
What type of cell is the precursor to the helper T cell?
CD4 cell
Which of the following activate CD8 cells?
antigen fragments on class I MHC proteins
What type of T cell can directly attack and kill other cells, such as virus-infected cells?
cytotoxic T (TC) cells
Which of the following are NOT appropriately matched?
helper T cells: destroy infected cells
B cell
Forms antibody producing cells
Regulatory T cell
Slows or stops the immune response
Helper T cell
Absence results in no immune response
Cytotoxic T cell
Kills cancer cells and virus infected body cells
Memory cell
Enables quick and efficient response to secondary exposure to antigen
T-cell activation requires ________.
antigen binding and co-stimulation
What occurs if a T cell binds to an antigen and the T cell does NOT receive a co-stimulatory signal?
The T cell enters a state of anergy.
Which lymphocytes act as the bridge between the cellular and humoral responses?
helper T cells