Exam 4 Flashcards
what do helper T cells activate?
B and other T cells
what do plasma cells secrete
antibodies
The region of each antibody molecule where amino acid composition is very different from one clone of B lymphocytes to another is the
variable region
antigen presenting cells
all of the answer choices are correct
Which process involves antibodies covering surface receptors on a virus or toxin molecule thereby disrupting their activity?
neutralization
The immunoglobulin class that has a dimer form found in mucus, saliva, colostrum, and other body secretions is
IgA
The immunoglobulin class that is the only one capable of crossing the placenta is
IgG
The immunoglobulin class that has an Fc region that binds to receptors on basophils and mast cells is
IgE
All of the following are characteristics of IgM, except
its a dimer
Which immunoglobulin class/es can fix complement?
IgM and IgG
An example of artificial passive immunity would be
giving a person immune serum globulins to chickenpox virus after exposure to the disease.
An example of natural passive immunity would be
a fetus acquiring maternal IgG to the chickenpox virus across the placenta.
In the primary response to an antigen, the first class of antibody to be secreted is
IgM
In the secondary response to an antigen, the predominant antibody is
IgG
Which kind of T-cell synthesizes perforins and granzymes to destroy viral infected cells, and cancer cells?
TC
In __________ immunity, an individual makes their own antibodies in response to antigen exposure, whereas in __________ immunity, an individual receives antibodies made by another individual(s).
active; passive
Antibodies against chicken-pox virus will protect against subsequent chicken-pox infections but not against measles. This is because antibodies are
specific
Components of the first line of defense include all the following, except
phagocytic white blood cells.
Nonspecific chemical defenses include
all of these choices are correct
The body region where a ciliary escalator helps to sweep microbes trapped in mucus away from that body site is the
repiratory tract
The blood cells that particularly target parasitic worms and fungi are
eosinophils
The clearance of pus, cellular debris, dead neutrophils, and damaged tissue after inflammation is performed by
macrophages
All of the following pertain to platelets, except
They contain hemoglobin to transport oxygen and carbon dioxide.
Which of the following lymphoid organs has the immunological function of filtering pathogens from the blood?
spleen
Which structures are found along lymphatic vessels but are heavily clustered in the armpit, groin, and neck?
lymph nodes
Which is incorrect about complement?
Complement proteins only appear in the blood during a response to a pathogen.
Specificity and memory are associated with which body defense mechanism?
T-cell and B-cell responses
All of the following are types of agranulocytes because they do not have prominent granules in their cytoplasm when stained, except
basophils
Which of the following nonspecific mediators inhibits virus replication and cellular division while increasing some lymphocyte action?
IFN
All of the following are the results of complement activation, except
lysis
Substances that are naturally produced by certain microorganisms that can inhibit or destroy other microorganisms are called
Antibiotics
Important characteristics of antimicrobic drugs include
All answer choices are correct
Broad-spectrum drugs that disrupt the body’s normal microbiota often cause
Superinfections
Penicillins and cephalosporins
block the peptidases that cross-link glycan molecules.
Sulfonamides
are metabolic analogs of PABA and block folic acid synthesis.
Aminoglycosides
attach to the 30S ribosomal subunit and disrupt protein synthesis.
Gram-negative bacilli are often treated with
aminoglycosides.
Which of these drugs is used to treat cases of tuberculosis?
isoniazid.
Which antimicrobic does not interfere with protein synthesis?
Trimethoprim
The drug used for several protozoan infections is
metronidazole
Ketoconazole, fluconazole, clotrimazole, and miconazole are broad-spectrum azoles used to treat _____ infections.
Fungal
Antivirals that target reverse transcriptase would be used to treat
HIV
The cellular basis for bacterial resistance to antimicrobics include
All of the answer choices are correct
The multidrug-resistant pumps in many bacterial cell membranes cause
removal of drugs from the cell
Antimicrobics effective against only gram-positive bacteria would be termed
Narrow spectrum drugs
One of the greatest challenges in development of antivirals is finding drugs that are
selectively toxic for viruses
Which is the best guide for selecting an effective antibiotic?
Results of antimicrobial susceptibility testing
Which of the following inhibits folic acid synthesis?
Trimethoprim
Which of the following types of control agents would be most likely to achieve sterility?
Sporicide
The process that destroys or removes all microorganisms and microbial forms including bacterial endospores is called
Sterilization
Which of the following microbial forms have the highest resistance to physical and chemical controls?
Bacterial endoscopes
The process of physically cleansing inanimate surfaces to reduce microorganisms and debris to safe levels is called
Sanitization
The use of chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is
Antiseptic
Scrubbing or immersing the skin in chemicals to reduce the numbers of microbes on the skin is called
Degermination
The easiest microbial forms to kill or inhibit are
Mycobacterium and staphylococcus
What type of molecule can be denatured by heat or changes in pH?
Protein
Physical agents for controlling microbial growth include all of the following except
Hydrogen peroxide
Disinfection of beverages, such as apple juice, milk, and wine, is optimally achieved by
Pasteurization
All of the following are true of food irradiation except
it makes the food less nutritious.
You are a scientist isolating a particular microbe from a water sample. As a first step, you need to inoculate a broth culture with your microbe using a sterile loop. Which of the following is the most appropriate way to sterilize your loop before inoculation? Consider effectiveness, time, and safety.
Sterilize the loop by using a bunsen burner at your bench.
