Chapter 3 - cellular adaptation, injury, and death

atrophy

cells shrink in size due to work demand

hypertrophy

increase in cell size

Hyperplasia

increase in number of cells

Metaplasia

a change in cell types in order to protect the skin (i.e. callous)

Dysplasia

abnormal change in cell shape (could be an indication of cancer not always)

Cellular Adaptation

allows the stressed tissue to survive or maintain function

examples of physical injury agents

mechanical forces (car accident, extreme temperature changes (frostbite), electrical forces (electrocution)

examples of radiation injury

ionizing radiation (Chernobyl disaster), ultraviolet radiation (sunburn), nonionizing radiation (microwaves)

examples of chemical injury

drugs, lead toxicity, carbon tetrachloride, mercury

hypoxic cells

deprives cells of oxygen and interrupts oxidative metabolism and the generation of atp

hypoxia results

acute cellular swelling

the longer a tissue is hypoxic...

the greater the chance of irreversible cellular injury

what are the causes of hypoxia

inadequate oxygen in the air, respiratory disease, edema, inability of cells to use oxygen, ischemia

what is edema

swelling caused of fluid imbalance which results in pushing on tissues

what is ischemia

lack of blood flow

apoptosis

cellular suicide, normal and protective function of the human body that does not stimulate the inflammatory process

what kind of cells are eliminated in apoptosis

worn out, cells produced in excess, developed improperly, genetic damage

necrosis

cell death in an organ/tissue that is a part of a living person

what does necrosis interfere with

cell replacement and tissue regeneration

gangrene

considerable mass of tissue undergoes necrosis

dry gangrene

tissues become dry and wrinkled, shrink, and become a dark brown/black spread is very slow

wet gangrene

area has a secondary bacterial infection, spread is very rapid and will result in death if not treated

why does wet gangrene spread so quickly

there is still blood flow in the area so the disease will spread quickly through the body