CPA #17 Questions

Question 1

Define: phagocytosis

Answer 1

“eating of a cell”; a way some microbes obtain nutrients; phagocytes use this to rid the body of pathogens to protect the body

Question 2

what are the 6 steps of phagocytosis?

Answer 2

1. chemotaxis
2. adhesion
3. ingestion
4. maturation
5. killing
6. elimination

Question 3

define: chemotaxis

Answer 3

movement of a cell either toward or away from a chemical stimulus (toward = positive; away = negative)

Question 4

define: adhesion (phagocytosis)

Answer 4

at site of infection; phagocytes attach to microorganisms through binding of complementary chemicals; pathogens are more readily phagocytized if they are covered with antimicrobial proteins (opsonins)

Question 5

define: opsonins

Answer 5

antimicrobial proteins that cover the pathogen allowing for phagocytosis

Question 6

define: opsonization

Answer 6

the process of covering pathogens with antimicrobial proteins

Question 7

define: ingestion (phagocytosis)

Answer 7

after adhering to pathogens, phagocytes extend pseudopods to surround microbe; pseudopods fuse together to form food vesicle (phagosome)

Question 8

define: maturation (phagocytosis)

Answer 8

lysosome adds digestive chemicals to the maturing phagosome (phagolysosome)

Question 9

define: phagolysosome

Answer 9

contain antimicrobial substances & 30+ different enzymes to destroy the engulfed microbes

Question 10

define: killing (phagocytosis)

Answer 10

phagolysosome kills the engulfed microbe

Question 11

define: elimination (phagocytosis)

Answer 11

phagocytes eliminate the remaining portions of microbe via exocytosis

Question 12

define: eosinophilia

Answer 12

abnormally high number of eosinophils in the blood (typically from helminth infestation or allergies)

Question 13

unusual action that eosinophils can perform

Answer 13

lipopolysaccharide from Gram- bacteria trigger eosinophils to rapidly eject mitochondrial DNA to combine with eosinophil proteins to create a barrier; this barrier binds to and kills the bacteria

Question 14

define: NK cells

Answer 14

natural killer lymphocytes; defensive leukocyte; innate immunity

Question 15

explain NK cell function

Answer 15

secretes toxins onto surfaces of virally infected cells and neoplasms (tumors); identify and spare normal body cells due to similarities with the proteins of NK cells; naturally programmed to kill other cells

Question 16

define: neutrophil NETs

Answer 16

neutrophil extracellular traps; extracellular fibers; cellular suicide involving disintegration of own nuclei

Question 17

how can neutrophils kill by forming NETs

Answer 17

as the neutrophil cell dies, the NETs are released, trapping Gram- & Gram+ bacteria along with antimicrobial peptides, killing the bacteria

Question 18

define: inflammation

Answer 18

general, non-specific response to tissue damage resulting from a variety of causes, including heat, chemicals, UV, pathogens, etc.

Question 19

define: acute inflammation

Answer 19

develops quickly, short lived, typically beneficial, and results in the elimination of whatever condition caused it (helpful)

Question 20

define: chronic inflammation

Answer 20

causes damage, sometimes death, to tissues, resulting in disease (harmful)

Question 21

what are the 4 signs and symptoms of inflammation?

Answer 21

1. redness (rubor)
2. localized heat (calor)
3. edema (swelling)
4. pain (dolor)

Question 22

define: vasodilation

Answer 22

increase in diameter of blood vessels in affected region

Question 23

which s+s of inflammation is vasodilation involved in?

Answer 23

all 4; increased dilation causes the redness + local heat; the increased permeability of venules can lead to increased fluid in surrounding tissues, causing edema + pain

Question 24

what chemical causes vasodilation of arterioles?

Answer 24

histamine

Question 25

what cells secrete histamine?

Answer 25

basophils, platelets, and mast cells

Question 26

define: fever

Answer 26

body temp above normal (above 37C)

Question 27

what controls fever?

Answer 27

hypothalamus

Question 28

what chemicals are secreted that affect fever?

Answer 28

pyrogens

Question 29

define: pyrogens

Answer 29

chemicals that trigger the hypothalamus to reset at a higher temp; include bacterial toxins, antibody-antigen complexes

Question 30

why do chills occur with fever?

Answer 30

as the fever progresses, blood vessels on the skin constrict (vasoconstriction); less blood to the skin causes them to feel cold to the touch and less red

Question 31

define: antigen

Answer 31

portions of of cells, viruses, and parts of single molecules that the body recognizes as foreign and worthy of attack; biochemical shapes

Question 32

define: epitopes

Answer 32

the 3D shape of a region of an antigen; determine the immune response caused; aka antigenic determinants

Question 33

what are the 3 types of antigens?

Answer 33

1. exogenous antigens
2. endogenous antigens
3. autoantigens

Question 34

define: exogenous antigens

Answer 34

come from outside the body’s cells and include toxins and other secretions/components of microbial cell walls, membranes, etc.

Question 35

define: endogenous antigens

Answer 35

produced by protozoa, fungi, bacteria, and viruses that reproduce inside a body’s cells; the immune system cannot assess the internal health of the body’s cells; only responds when the antigens are incorporated into cytoplasmic membrane

Question 36

define: autoantigens

Answer 36

derived from normal cellular processes; aka self-antigens

Question 37

define: self-tolerance

Answer 37

process of eliminating immune cells that attack autoantigens; which prevents the body from starting an immune response against itself

Question 38

define: antibodies

Answer 38

free immunoglobulins (not attached to a membrane); ‘Y’ shaped; bind with antigens

Question 39

define: agglutination

Answer 39

multiple antibodies can aggregate antigens together

Question 40

define: ABO system

Answer 40

two antigens (‘A’ and ‘B’); RBCs have either A/B, A+B, or neither (‘O’)

Question 41

define: transfusion reactions

Answer 41

the blood recipients own immune system attacks the donor blood; the donor blood triggers the reaction

Question 42

define: hemolysis

Answer 42

rupturing of blood cells; can occur during a transfusion reaction

Question 43

define: Rh antigen

Answer 43

on outside of blood cell, either +/- ; 85% of population is Rh+ and 15% is Rh-

Question 44

define: RhoGAM

Answer 44

anti-Rh immunoglobulin (IgG) which destroys the fetal cells before they can trigger an immune response

Question 45

define: hemolytic disease of newborn

Answer 45

Rh- mother is pregnant with Rh+ baby; fetal blood cells escape into mothers bloodstream and trigger immune response