Cell injury and tissue death Flashcards
Definition: Cell injury
The biochemical and/or morphological changes that occur when the steady state is perturbed (unsettles) by adverse inflences
What is hyperplasia?
The increase in the number of cells
What is hypertrophy?
The increase in the cells size
What 2 things can increase cellular activity?
Either hyperplasia or hypertrophy
What is atrophy?
When the cell shirnks either in size or number due to a decreased demand
What is metaplasia?
When cells change their shape/morphology, which consequently changes their function (for example this occurs in the cervix)
What is anoxia?
No O2 supply
What is ischemia?
Inadequate blood supply to an organ or part of the body
Physical trauma can damage cells. An example of this is extremes of temperatures.
Ice crystals can disrupt cell membranes.
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What is an exotoxin?
Toxins released by a living bacterial cell into its SURROUNDINGS
What is a endotoxin?
A toxin present INSIDE a bacterial cell that is released when it disintegrates
What is cell lysis?
Disintegration of a cell by rupture of the cell wall or membrane.
It is caused by a virus hijacking the cell
How does ionising radiation (irradiation) damage cells?
Ionising radiation will knock off an electron, which generates a free radical. This free radical will bind to macromolecules (molecules containing a large number of atoms, for example proteins or nucleic acids).
Often, free radicals can generate more free radicals, which can cause a chain reaction.
What type of enzyme detoxifies free radicals?
Superoxide dismutase, and also the vitamins A, C and E
In what example is free radical injury useful?
Neutophils and macrophages generate free radicals inside the phagosomes to kill the bacteria