64 terms


Structure and Function of the Organs of Defense and Immunity
1. Components of the first line of defense include all the following except:
A) the tough cell sheet of the upper epidermis of the skin
B) nasal hairs
C) flushing action of tears and blinking
D) flushing action of urine
E) phagocytic white blood cells*
2. Nonspecific chemical defenses include:
A) lysozyme
B) lactic acid and electrolytes of sweat
C) skin's acidic pH and fatty acids
D) stomach hydrochloric acid
E) all of the choices are correct*
3. The chemical found in tears and saliva that hydrolyzes the peptidoglycan in certain bacterial cell walls is:
A) lactic acid
B) hydrochloric acid
C) lysozyme*
D) histamine
E) bile
4. The body region where a ciliary escalator helps to sweep microbes trapped in mucus away from that body site is the:
A) skin
B) respiratory tract*
C) digestive tract
D) urinary tract
E) eyes
5. This body region is protected by fatty acids, acidic pH, lactic acid, and a tough cell barrier with its own normal flora:
A) skin
B) respiratory tract
C) digestive tract*
D) urinary tract
E) eyes
6. Plasma:
A) is the liquid portion of blood in which blood cells are suspended
B) is mostly water
C) contains albumin and globulins
D) contains fibrinogen
E) all of the choices are correct*
7. Which is incorrect about blood cells?
A) after birth produced in red bone marrow sites
B) develop from undifferentiated stem cells
C) include mast cells*
D) include leukocytes that are either granulocytes or agranulocytes
E) include erythrocytes that, when mature, lose their nuclei
8. The blood cells that function in allergic reactions and inflammation, contain peroxidase and lysozyme, and particularly target parasitic worms and fungi are:
A) basophils
B) eosinophils*
C) neutrophils
D) monocytes
E) lymphocytes
9. The least numerous of all white blood cells, that release histamine during inflammation and allergic reactions are:
A) basophils*
B) eosinophils
C) neutrophils
D) monocytes
E) lymphocytes
10. Comprise 20% to 30% of the circulating WBC's, and are the cells that function in the body's immune system:
A) basophils
B) eosinophils
C) neutrophils
D) monocytes
E) lymphocytes*
11. The most numerous WBC's, that have multilobed nuclei and are very phagocytic are:
A) basophils
B) eosinophils
C) neutrophils*
D) monocytes
E) lymphocytes
12. Comprise 3-7% of circulating WBC's, are phagocytic, and can migrate out into body tissues to differentiate into macrophages:
A) basophils
B) eosinophils
C) neutrophils
D) monocytes*
E) lymphocytes
13. All of the following pertain to platelets except:
A) contain hemoglobin to transport oxygen and carbon dioxide*
B) also called thrombocytes
C) originate from giant multinucleate cells called megakaryocytes
D) function in blood clotting and inflammation
E) they are not whole cells but are pieces of cells
14. Hemopoiesis is the
:A) loss of blood due to hemorrhaging
B) production of only red blood cells
C) production of white blood cells, red blood cells, and platelets*
D) plugging of broken vessels to stop bleeding
E) migration of white blood cells from the blood out to the tissues
15. Diapedesis is the:
A) loss of blood due to hemorrhaging
B) production of only red blood cells
C) production of white blood cells, red blood cells, and platelets
D) plugging of broken vessels to stop bleeding
E) migration of intact white blood cells from between endothelial cells of a blood vessel such as a venule out to the tissues*
16. Plasma cells:
A) function in cell-mediated immunity
B) are derived from T-lymphocytes
C) function in blood clotting
D) produce and secrete antibodies*
E) all of the choices are correct
17. The reticuloendothelial system:
A) is a support network of connective tissue fibers
B) originates in the cellular basal lamina
C) provides a passageway within and between tissues and organs
D) is heavily populated with macrophages
E) all of the choices are correct*
18. Which of the following lymphoid organs and tissues has the immunological function of filtering pathogens from the blood?
A) lymph nodes
B) thymus
C) spleen*
E) tonsils
19. These structures are found along lymphatic vessels but are heavily clustered in the armpit, groin, and neck:
A) lymph nodes*
B) thymus
C) spleen
E) tonsils
20. This gland shrinks in size during adulthood, and has hormones that function in maturation of T-lymphocytes:
A) lymph nodes
B) thymus*
C) spleen
E) tonsils
21. The lymphoid tissues of the intestinal tract are collectively referred to as:
A) lymph nodes
B) thymus
C) spleen
E) tonsils
22. The four classic signs and symptoms of inflammation include all the following except:
A) redness
B) warmth
C) swelling
D) pain
E) chills*
23. All the following are events of early inflammation except:
A) macrophages appear first and begin phagocytosis*
B) chemical mediators and cytokines are released
C) brief vasoconstriction is followed by vasodilation
D) exudate and pus can accumulate
E) capillaries become more permeable resulting in edema
24. Which is incorrect about inflammation:
A) can last hours to years*
B) pyrogens cause vasodilation and increased capillary permeability*
C) serotonin causes smooth muscle contraction
D) fever could be beneficial to inhibiting the pathogen
E) basophils and mast cells release histamine
25. Which is mismatched:
A) interferon alpha and beta - inhibits viral replication
B) interleukin-2 - stimulate T cell mitosis and B cell antibody production
C) serotonin - causes smooth muscle contraction
D) prostaglandins - activate eosinophils and B cells*
E) tumor necrosis factor - increases chemotaxis and phagocytosis
26. Histamine, serotonin, and bradykinin are all:
A) vasoactive mediators*
B) mediators of B cell activity
C) mediators of T cell activity
D) mediators that increase chemotaxis
E) fever inducers
27. These white blood cells are particularly attracted to sites of parasitic infections:
A) monocytes
B) eosinphils*
C) basophils
D) neutrophils
E) lymphocytes
28. When opsonization accompanies phagocytosis, this process involves:
A) formation of a phagolysosome
B) myeloperoxidase giving rise to OCl-
C) antibodies or complement coating the microbial cell surface
D) the liberation of lysozyme
E) neutrophils but not macrophages
29. All of the following pertain to interferon except:
A) protein
B) produced by certain white blood cells and tissue cells
C) includes alpha, beta, and gamma types
D) inhibit viruses, tumors, and cancer gene expression
E) increase capillary permeability and vasodilation*
30. The circulating substances that affect the hypothalamus and initiate fever are:
A) complement
B) interferons
C) leukotrines
D) pyrogens*
E) lysozymes
31. Which is incorrect about complement?
A) composed of at least 26 blood proteins
B) only appear in the blood during a response to a pathogen*
C) act in a cascade reaction
D) involves a classical pathway
E) involves an alternate pathway
32. The membrane attack stage of the complement cascade involves:
A) initiation of the cascade
B) production of inflammatory cytokines
C) a ring-shaped protein digests holes in bacterial cell membranes and virus envelopes*
D) cleaving of C3 to yield C3a and C3b
E) C1q binds to surface receptors on a membrane
33. Specificity and memory are associated with which body defense mechanism?
A) inflammatory response
B) phagocytosis by macrophages and neutrophils
C) interferon
D) T cell and B cell responses*
E) anatomical barriers in the body
34. Genetic differences among species, and within a species, can convey genetic immunity to certain diseases.
A) True*
35. Plasma is also called lymph.
B) False*
36. B lymphocytes and T lymphocytes mature in the thymus gland.
B) False*
37. Monocytes and lymphocytes are agranular leukocytes.
A) True*
38. During inflammation, a high neutrophil count is a common sign of bacterial infection.
B) False
39. Complement proteins are produced by the spleen.
B) False
40. Certain complement components stimulate inflammation and phagocytosis.
A) True
41. Inflammatory responses are orchestrated by the immune system and are part of the body's third line of defense.
B) False
42. Endotoxin is an exogenous pyrogen.
A) True
43. During phagocytosis, intracellular digestion begins as soon as the phagosome is formed.
B) False
44. Neutrophils, eosinophils, and basophils are called _____ because they have prominent cytoplasmic granules that, in a stained blood smear, appear with identifying, characteristic colors.
45. _____ lymphocytes function in humoral immunity, while _____ lymphocytes function in cell-mediated immunity.
B, T
46. The _____ region of a lymph node has germinal centers packed with T and B lymphocytes.
47. When monocytes migrate from the blood out to the tissues they are transformed by inflammatory mediators to develop into _____.
48. A person will typically experience the sensation of _____ when fever is starting to occur in the body.
49. The term _____ is given to any foreign matter/protein/substance that stimulates a specific immune system response.
50. The _____ system of blood proteins act to lyse foreign cells and viruses.
1st line of defense -
intact skin
mucous membranes & their secretions
2nd line of defense - nonspecific
phagocytic white blood cells
inflammation -complement
fever -interferon
3rd line of defense - specific
B & T lymphocytes
B lymphocytes will become plasma cells that secrete antibodies (specific)
Genetic defenses
Some hosts are genetically immune to the diseases of other hosts, species specific
Some pathogens have great specificity, areas of attachment present, identifying markers
Some genetic differences exist in susceptibility, prone to cancer, etc.
A healthy immune system is responsible for
-Surveillance of the body
-Recognition of foreign material
-Destruction of entities deemed to be foreign (NOT SELF)
Characteristics of leukocytes - Diapedesis
migration of cells out of blood vessels into the tissues
migration in response to specific chemicals at the site of injury or infection
helping prevent spread of infection
Activities of phagocytes
To survey tissue compartments & discover microbes, particulate matter & dead or injured cells
To infest and eliminate these materials
To extract immunogenic information from foreign matter
Interferons (IFNs
are small natural proteins produced by the cells of the immune system of most vertebrates in response to challenges by foreign agents such as viruses, parasites, and tumor cells.
Interferons belong to the large class of glycoproteins known as cytokines.
Interferons are produced by a wide variety of cells in response to the presence of double-stranded RNA and various antigens, a key indicator of viral infection.
Interferons assist the immune response by inhibiting viral replication within host cells, activating natural killer cells and macrophages, increasing antigen presentation to lymphocytes, and inducing the resistance of host cells to viral infection
When the antigen is presented to matching T and B cells, they multiply and strategically and specifically wipe out that particular foreign substance.
Inhibit expression of cancer genes
Consists of 26 blood proteins that work in concert to destroy bacteria and viruses BY PRODUCING PORES IN THE MEMBRANE
Complement functions through a cascade reaction (initiation, amplification, & membrane attack) which is a sequential physiological response
Classical pathway and Alternative pathway differ in how they are activated, speed and efficiency, the 2 pathways will merge
Certain complement components stimulate inflammation and phagocytosis.
Classical pathway - antibody presence, more efficient
Alternative pathway - bind to normal cell walls, slower and less efficient
B and T lymphocytes - react to only one specific antigen
Specificity and memory - highly selective
Immunocompetence - the ability of the body to react with a variety of foreign matter, an infant is born with the potential to acquire millions of different immunities
Cell-mediated response
A type of immunological reaction carried out by cytotoxic T cells. A cell infected with foreign antigens, possibly through viral infection, presents the antigen on the surface of the cell bound to a major histocompatibility complex (MHC) protein. The T cell receptor recognizes both the antigen and the MHC protein and consequently may attack the infected cell or invading extracellular particles.
Humoral response
An antibody-mediated immunoresponse. Antibodies are secreted by B cells that have been stimulated by helper T cells. Antibodies bind to foreign antigens which they recognize, to form an antibody-antigen complex. The resulting complex may then be consumed by a macrophage.