Phagocytosis Flashcards
Process by which specialized cells engulf and destroy foreign particles such as microorganisms or damaged cells.
Phagocytosis
Most important phagocytic cells
Macrophages and Neutrophils
A cell that ingests microorganisms and foreign particles.
Phagocytic cells
Extremely small, relatively simple prokaryotic microorganisms traditionally classified with the fungi as Schizomycetes.
Bacteria
Something that suggests the presence or existence of a fact, condition, or quality
Signs
Any indication of a disease or injury perceived by the patient
Symptoms
The site of the experiment should be..
Sterilized
Blood should be drawn by an…
Aseptic technique
A minimum of 2 ml of blood is put into the
Green-top evacuated tube
A green top tube has what kind of anti-coagulant
Heparin
(True or False)
The microscope shouldn’t be placed on a plain, stable surface.
False
(True or False)
The voltage of the power supply should be inclined with that of the equipment.
True
What organism should we use in this experiment
Bacillus subtilis or Staphylococcus epidermidis
What stain is used in the experiment
Wright stain
How many drops of buffy coat should be added
4-8 drops
How many drops of bacterial broth culture is added?
2-3 drops
(True or False)
Place 2 drops of the incubated specimen on a glass slide and prepare a smear.
False
(Interpret)
Demonstration of the engulfment of bacteriaz
Positive
(Interpret)
No engulfment of bacteria
Negative
(True or False)
The procedure may produce false-negative results if the blood specimen is not fresh.
True
(True or False)
Coagulase-positive Staphylococcus specimen may produce false-positive results.
True
(Interpret)
Bacteria is not intracellular
Negative
(True or False)
The bacteria must be intracellular and not extracellular for the test to be positive.
True
The failure of phagocytes to engulf bacteria can support the diagnosis of what?
Neutrophilic dysfunction
Action of a specialized group of phagocytic cells that provide a defense mechanism against invasion by engulfing foreign particulate matter.
Phagocytosis
Constitute the major cellular components (mast cells, neutrophils, macrophages)
Phagocytes
Activated phagocytes have increased surface receptors that allow for adherence to the bacterium
Initiation
Process in which cells tend to move in a certain direction under the stimulation of chemical substance.
Chemotaxis
Shows positive chemotaxis
Leukocytes
Away from the stimulating substances
Negative Chemotaxis
Toward the stimulating substances
Positive Chemotaxis
By active ameboid motion; final structure is known as vacuole/phagosome; bacteria must be hydrophobic than the phagocyte
Engulfment
Interact with the surfaces of bacteria, rendering them acceptable to the phagocyte
Opsonin
Engulfment of antigen
Phagosome
Fusion of phagosome and lysosome
Phagolysosome
Minute cell particles that contain certain hydrolytic enzymes and peroxides approach the phagosome, fuse with it, rupture, and discharge content to it.
Digestion
Has defensins and cathepsin-G
Oxygen independent
Formation of superoxide —> hydrogen peroxide —> hypochlorite
Oxygen dependent (oxidative burst)
Physical contact between the phagocytic cell and the microorganism occurs, aided by opsonins.
Adherence
Outflowing of cytoplasm to surround the microorganism
Engulfment
Microorganism is completely surrounded by a part of the cell membrane.
Formation of phagosome
Lysosomal granules contact and fuse with the phagosome.
Granule contact
Contents of the lysosome are emptied into this membrane-bound space.
Formation of phagolysosome
Uses hydrolytic enzymes
Digestion of microorganisms
Contents of phagolysosome are expelled to the outside by exocytosis
Excretion
