BIO 205 - Final Flashcards
1
Q
abscess
A
pus-filled legion
2
Q
complement
A
group of 30 blood proteins activated as a cascade; assist pathogen elimination by stimulating inflammation and enhancing phagocytosis; lyse pathogens by forming membrane attack complexs
3
Q
edema
A
swelling of tissues caused by build-up of fluid
4
Q
fever
A
high body temp caused by bacterial/viral infection
5
Q
inflammation
A
nonspecific defensive response to injury characterized by redness, warmth, swelling, and pain
6
Q
interferon
A
virus defense; a cytokine that fights infection; triggers an antiviral state against viral infections
7
Q
leukocyte
A
white blood cell
8
Q
leukocytosis
A
elevated WBCs; more than 10,500 = infection
9
Q
leukopenia
A
decreased WBCs; lower than 3500 = infection or at risk for infection (TB/AIDS)
10
Q
lymph node
A
organ involved in immune response and contains phagocytes and lymphocytes
11
Q
lymphocyte
A
type of WBC (B cells, T cells) 20-30% of WBCs; function = antibodies and cell defenses
12
Q
macrophage
A
large cell derived from monocytes found within various tissues and actively engulfs foreign material, including infecting bacterial cells and viruses
13
Q
monocyte (blood monocyte)
A
tissue marcophage; a circulating WBC with a large bean-shaped nucleus that is the precursor to a macrophage; long-lived; function = antigen presentation
14
Q
mucous membrane
A
moist lining in the body passages of all mammals that contain mucus-secreting cells and is open directly or indirectly to the external environment
15
Q
mucus
A
sticky secretion of glycoproteins
16
Q
neutrophil
A
type of phagocyte (50-70% of WBCs) functions chiefly to engulf and destroy foreign material, including bacterial/viral cells; short-lived
17
Q
phagocyte
A
includes neutrophils, blood monocytes, and dendritic cells; WBC capable of engulfing and destroying foreign materials, including bacterial/viral cells
18
Q
dendritic cell
A
type of phagocyte having long extensions; found in all tissues; engulfs foreign material/bacteria/viruses through phagocytosis and presents antigen peptides on surface; 1% of WBCs
19
Q
phagocytosis
A
process by which foreign material or cells are taken into a WBC and destroyed
20
Q
pyrogen
A
fever-producing substance (cytokine)
21
Q
sebum
A
oily substance produced by the sebaceous glands that keep skin and hair soft and moist
22
Q
vasodilation
A
a widening of the blood vessels, especially the arteries, leading to increased blood flow; symptom of inflammation
23
Q
cytokine
A
small proteins released by immune defensive cells that affect other cells and the immune response to an infectious agent; includes attraction cytokines, pyrogen cytokines, and interferon cytokines
24
Q
Explain the importance of primary and secondary lymphoid tissues and the role of lymph nodes as a defense against pathogens
A
- Primary lymphoid tissues = thymus and bone marrow; this is where lymphocytes mature (B/T cells, antibodies & cell defenses)
- Secondary lymphoid tissues = lymph nodes, spleen, tonsils & adenoids; where immune battles occur
- Lymph nodes contain phagocytes (engulf & destroy) and lymphocytes (antibodies & cell defense)
25
What is the importance of the innate immune response?
-Innate immune response = nonspecific resistance; found in all animals; born with the resistance; provides same response to any pathogen, abnormal cell, or foreign material (nonspecific); first line of defense = physical, chemical, cellular; second line defenses = acquired immunity found only in vertebrates
26
List and describe the physical, chemical, and microbiological barriers against infection involved with innate immunity.
- Physical = skin; mucous membranes which provide mucus which is coughed/sneezed out of the body
- Chemical = bactericidal components: skin oils (sebum), sweat lysozome & other defense proteins, stomach acid
- Cellular = normal microbiota, WBCs
27
Explain the process of phagocytosis and identify the types of leukocytes involved
1) attachment and entry of pathogen
2) endocytosis (brings pathogen into cell forming phagosome
3) fusion with lysosomes (phagolysosome)
4) pathogen destruction
5) elimination of wastes
28
Define inflammation and describe the stages
Inflammation = nonspecific response to trauma characterized by redness(R), warmth(W), swelling(S), and pain(P)
1) firs line breached; cytokines secreted by macrophages
2) capillary vasodilation brings plasma to site; tissue edema (R,W,S,P)
3) more phagocytes arrive (monocytes mature into macrophages); phagocytosis occurs
4) abscess forms as tissue repair occurs (P)
29
What is the cause and effect of fever on an infection or disease?
Fever = caused by pyrogens; consist of microphage (released cytokines that tell the body to turn up the temp) and bacterial fragments or toxins/viruses; act on the hypothalamus; moderate fever (102-103 F) can be a good thing because it speeds tissue repair and phagocytosis and inhibits pathogen replication
30
Describe how complement functions as an antimicrobial defense system
Complement = group of 30 blood proteins activated as a cascade; assist pathogen elimination by stimulating inflammation and enhancing phagocytosis; lyse pathogens (bacteria) by forming membrane attack complexes
31
Explain how interferon puts cells in an antiviral state
1) Virus infects cell
2) Infected cell responds by producing and secreting interferon
3) Interferon sensed by neighboring cells
4) Responding cells produce antiviral proteins (AVPs) = antiviral state
5) When virus infects neighboring cell, AVPs destroy viral genome
32
The secondary lymphoid tissues include what?
spleen and lymph nodes
33
Why is the stomach a chemical barrier to infection?
Because the stomach has an acid pH
34
What are pyrogens?
Proteins affecting the hypothalamus; bacterial fragments, and fever-producing substance
35
What is produced in response to a viral infection?
interferon
36
Small protein released by various defensive cells in response to an activating substance?
cytokine
37
A T cell or B cell is one.
lymphocyte
38
A monocyte matures into one of these
macrophage
39
Found in human tears and sweat
lysozyme
40
Also called a PMN
neutrophil
41
Refers to a substance causing fever
pyrogen
42
A short-lived phagocyte
neutrophil
43
Summarize MicroFocus 20.1: "Who Turned On the Spigot?"
-Runny nose/sniffles is body's first line of defense against an infection; the mucus washes out the respiratory pathogens in the airways; healthy individuals produce and swallow about 200 mL mucus/day; sick people can produce up to 200mL/day; infection can cause the mucus to be thick and yellow; cold or flu causes the nasal passages to become congested forcing the mucus from the nostrils; tear duct liquid from watery eyes can combine with mucus; must drink lots of water to make up for phlegm lost
44
antibody
a highly specific protein produced by the body in response to a foreign substance, such as bacteria/virus, and capable of binding to the substance
45
antigen
chemical substance that stimulates the production of antibodies by the body's immune system
46
antigen binding site
the region on an antibody that binds to an antigen
47
antigen-presenting cell (APC)
a macrophage or dendritic cell that exposes antigen peptide fragments on its surface to T cells
48
B cells (B lymphocytes)
WBC that matures into memory cells and plasma cells that secrete antibody
49
bone marrow
a soft reddish substance inside some bones that is involved in the production of blood cells
50
clone
population of genetically identical cells (or plasmids)
51
cytokine
small proteins released by immune defensive cells that affects other cells and the immune response to an infectious agent
52
cytotoxic T cell
the type of T lymphocyte that searches out and destroys infected cells
53
epitope (antigenic determinant)
section of an antigen molecule that stimulates antibody formation and to which the antibody binds
54
heavy chain
larger polypeptide in an antibody
55
immunoglobulin (Ig)
class of immunological proteins that react with an antigen; an alternate term for antibody
56
light chain
smaller polypeptide in an antibody
57
memory cell
cell derived from B lymphocytes or T lymphocytes that reacts rapidly upon re-exposure to antigen
58
plasma cell
antibody-producing cell derived from B cells
59
thymus
organ where T lymphocytes mature
60
T cells (T lymphocytes)
WBC that matures in the thymus gland and is associated with cell-mediated immunity
61
List and describe the four basic characteristics of acquired immunity
1) Recognizes & responds to diverse foreign substances (antigens) = antigens: pathogen parts, toxins, tumor cells, transplants
2) Exhibits tolerance = "self" tolerated, "nonself" attacked (can differentiate between what is part of you and what is not)
3) Causes minimal damage to self = local sites of attack (secondary lymphoid tissues)
4) Maintains memory to previously fought antigens = immunity to future exposures to same pathogen
62
Define an antigen and an antigenic determinant
- Immune system recognizes epitopes on the antigen (epitope = parts of the antigen that are recognized by antibodies)
- Antigens are immunogenic (stimulate an immune response)
63
Describe how T and B cells bind antigens
B cells = originate & mature in bone marrow; migrate to secondary lymphoid tissues; responsible for humoral (antibody) immunity (make antibodies)
T cells = originate in bone marrow but mature in thymus; migrate to secondary lymphoid tissues; become helper T cells or cytotoxic cells; responsible for cell-mediated immunity
64
Describe how humoral immunity generates antibodies that are specific to a pathogen (antigen).
1) Antigens enter lymphoid organ
2) B & T cells reside in the lymphoid organs
3) Antigen binds to appropriate B cell (based on receptors)
4) Cytokines trigger division & clone formation
5) B cells form memory B cells & mature into plasma cells
6) Plasma cells secrete antibody into blood (antibody specific to infection)
7) Upon second exposure, B cells convert directly to plasma cells & clone more memory cells
* **Takes 2 weeks for seroconvert (time body responds & starts producing antibodies)
65
Identify and describe the characteristics of the immunoglobulin (Ig) classes.
1) IgG: 1 subunit; 80% in serum; complement activation; crosses placenta; phagocyte binding; function = fight infections w/in blood/lymph fluids
2) IgM: 5 subunits; 5% in serum; complement activation; does not cross placenta; phagocyte binding; function = fight infections w/in blood/lymph fluids
3) IgA: 2 subunits; 15% in serum; no complement activation; does not cross placenta; no phagocyte binding; function = secreted out of body (digestion, saliva, tears)
66
Explain how primary and secondary antibody responses confer immunological memory and immunity to infectious agents.
After the primary antigenic stimulation, IgM is the first antibody to appear in the circulation. Later, IgM is supplemented by IgG. On a secondary exposure to the same antigen, the production of IgG is more rapid, and the concentration in the serum reaches a higher level than in the primary response.
67
Describe and assess the mechanisms for antigen clearance through antibody interactions in the body.
1) Viral inhibition = antibodies react with molecules at the viral surface and prevent the viral attachment to cells
2) Neutralization = antibodies combine specifically with toxins (or microbes), thereby neutralizing them and preventing attachment to cells
3) Agglutination = antibodies combine with antigens on the cell surface and bind the cells together or restrict their movement
4) Phagocytosis = a portion on antibodies encourages phagocytosis by forming a bridge between antigen and receptor sites on the phagocyte
68
What is the ELISA blood test?
Test for antibodies to a pathogen (detects antibodies) for HIV/AIDS & Hepatitis C; only determines if someone has been exposed; disease must be fully seroconverted for accurate test
69
Explain how cell-mediated immunity reacts to trigger B cell activity and kill virus-infected cells
1) Antigen presenting cell presents antigen peptides to naive T cells
2) T cells divide into a clone of helper T cells
3) some clones become memory T cells
4) Some clones search out B cells
5) Clone of immature T cells "help" B cells trigger humoral immunity through cytokines
6) Some clones transform into cytotoxic T cells which search out infected cells
7) CTs find & destroy infected cells
70
active immunity
immune system responds to antigen by producing antibodies and specific lymphocytes
71
antiserum
blood-derived fluid containing antibodies and used to provide temporary immunity
72
antitoxin
an antibody produced by the body that circulates in the bloodstream to provide protection against toxins by neutralizing them
73
booster shot
a repeat dose of a vaccine given some years after the initial course to maintain a high level of immunity
74
conjugate vaccine
an antigen preparation consisting of the antigen bound to a carrier protein
75
herd immunity
the proportion of a population that is immune to a disease
76
passive immunity
the temporary immunity that comes from receiving antibodies from another source
77
serum
the fluid portion of the blood consisting of water, minerals, salts, proteins, and other organic substances, including antibodies; contains no clotting agents (plasma)
78
subunit vaccine
a vaccine that contains parts of microorganisms
79
toxoid
a preparation of a microbial toxin that has been rendered harmless by chemical treatment but that is capable of stimulating antibodies; used as vaccines
80
vaccination
inoculation with weakened or dead microbes or viruses in order to generate immunity
81
vaccine
a preparation containing weakened or dead microorganisms or viruses, treated toxins, or parts of microorganisms or viruses to stimulate immune resistance
82
whole agent vaccine
vaccine preparation that includes the entire microorganism and not just parts (classical)
83
Contrast the forms of active and passive immunity
Active: 1) Naturally acquired by exposure to pathogen and recovery from illness 2) artificially acquired through vaccination
Passive: 1) Naturally acquired by passage of IgG antibodies across placenta 2) artificially acquired by injection of antiserum or antitoxin (antibodies from external source)
84
List the Whole Agent Bacterial/Viral Vaccines
Attenuated, inactivated, and toxoid
85
List the Modern Group Bacterial/Viral Vaccines
Subunit, conjugate, nucleic acid (DNA)
86
What is an attenuated vaccine?
Living but weakened pathogen; slight chance of virulence, "lifelong" immunity; used to treat chickenpox & measles, mumps, rubella (MMRs)
87
What is an inactivated vaccine?
chemically "killed" pathogen; virulence cannot redevelop; no "lifelong" immunity; used to prevent cholera and the flu
88
What is a toxoid vaccine?
Heat inactivated exotoxins; virulence cannot redevelop; no "lifelong" immunity (boosters; used to prevent tetanus, diptheria
89
What is a subunit vaccine?
A fragment of the pathogen; virulence cannot redevelop; possible "lifelong" immunity; used to prevent Hepatitis B and HPV
90
What is a conjugate vaccine?
polysaccharide + hapten (molecule attached to polysaccharide which stimulates and immune response); virulence cannot redevelop; no "lifelong" immunity (boosters); used to prevent HIB meningitis and pertussis
91
What is a Nucleic Acid (DNA) vaccine?
pathogen gene in a plasmid injected into individual; virulence cannot redevelop; not available to humans; used to prevent West Nile in horses
92
What is the usefulness of booster shots?
1) Re-establish "immunological memory" with B and T memory cells
2) elevates antibody levels in blood
93
Explain the generation of herd immunity and assess its role in disease prevention.
1) Results from immunizing most of a population (herd)
2) Breaks the chain of transmission
3) Herd immunity threshold = 85% vaccinated
4) Makes finding susceptible host difficult because most people are immune
94
Discuss the side effects that a vaccine may have?
1) Symptoms include: fever, malaise, soreness at injection site
2) Attenuated vaccines may pose problems for infants, pregnant women, and elderly
3) 1 in 1 million have a serious side effect
4) Polio vaccine = Sabin (attenuated, oral) versus Salk (inactivated, injected)
5) MMR vaccine = is safe (not linked to autism)
