tissue ischemia, extreme temperature exposures, radia-
tion exposure, physical tissue damage, chemical toxins,
cell stressors
microorganisms, abnormal accumulation of metabolites
in cells, nutritional deficits
1. ATP depletion: anaerobic metabolism - until glycogen
stores are depleted, Na/K ATPase & Ca ATPase are attected,
increased intracellular Na & Ca, H2O follows Na - Cell
swelling, RER swelling - ribosomes detach - decrease in
protein synthesis
2. Increased Intracellular Calcium: Ca activates intracellular
catabolic enzymes, decrease in ATP, membrane damage,
ettects of hypoxic cell injury
DNA damage, Increase in mitochondrial permeability -
increase in ROS
3. Oxygen-derived free radicals = ROS: destruction of cell
membrane & nucleus
4. Defects in Membrane Permeability: Leakage of intracel-
lular enzymes, can be detected in the blood
allows the stressed tissue to survive or maintain function
cellular adaption such as:
atrophy, hypertrophy, hyperplasia, metaplasia, dysplasia
Hypertrophy increase in cell size
increase in number of cells
Hyperplasia
the enlargement of an organ or tissue because of an
abnormal increase in the number of cells in the tissues
Metaplasia Mature cell type is replaced by a ditterent mature cell type
Dysplasia
,abnormal development or growth of cells, tissues, or or-
gans
Necrosis tissue death
Types of Necrosis coagulation, liquefaction, caseous
Coagulative necrosis Cell proteins are altered or denatured - coagulation
necrotic tissue has dissolved and is gone
Liquifactive necrosis a the of necrosis with liquefaction of neurons and glial
cells in the brain as a result of ischemic injury or bacterial
infection
degeneration and death of tissue with a cheese-like ap-
Caseous necrosis
pearance
Fat necrosis Fatty tissue is broken down into fatty acids
death of tissue from severe hypoxic injury
death of tissue from hypoxia, commonly from arteioscle-
Gangrenous necrosis rosis and attecting lower leg; may be be classified as dry,
where the skin appears brown and wrinkled, or wet, where
the skin appears cold, swollen and black as a result of
liquefactive necrosis occurring at the site
a form of coagulative necrosis that develops in ischemic
Dry necrosis tissue, where the blood supply is inadequate to keep
tissue viable
Wet Necrosis liquefactive necrosis (superimposed infection)
refers to the special type of gangrene caused by Clostrid-
ium
Gas necrosis
formation of air bubbles in the tissue
, A genetic disorder that is present at birth and attects both
Cystic fibrosis
the respiratory and digestive systems.
autosomal recessive trait meaning both parents carry a
recessive trait for the disease
How is cystic fibrosis inherited?
The allele is recessive. If both parents are carriers there is
a 25% chance that the ottspring will have CF.
a condition with symmetrical weakness and wasting of
pelvic, shoulder, and proximal limb muscles
Duchenne muscular dystrophy
A human genetic disease caused by a sex-linked recessive
allele; characterized by progressive weakening and a loss
of muscle tissue.
A genetic disorder caused by the presence of all or part of
Down Syndrome (Trisomy 21)
a third copy of chromosome 21.
What causes down syndrome? an extra chromosome 21
How many chromosomes does someone with down syn-
47 chromosomes
drome have?
How is Down Syndrome inherited? nondisjunction
an extra X chromosome causes physical abnormalities and
infertility
Klinefelter Syndrome (XXY)
underdeveloped sex organs, breast development, large
hands, and long arms and legs
Achondroplasia. Two variants (also called mutations) in
the FGFR3 gene cause more than 99 percent of cases
Dwarfism FGFR mutation
of achondroplasia, which is the most common form of
short-limbed dwarfism
Achondroplasia