ADVANCED PHYSIOLOGY &
PATHOPHYSIOLOGY EXAM
Levels of Cellular Injury
stress causes cell to adapt, but at some point it will eventually cause injury
injuries can lead to cell death, but at some point along cellular pathway, the
injury can be reversible
at some point, the injury becomes irreversible, and the cell will die, either by
apoptosis or necrosis
Stresses: mechanical forces (usually superficial injuries), electrical injuries,
(electricity can carry heat that damages, electrical impulses can change
electrical balance w/in body), nutritional imbalances, biological agents
(viruses/bacteria), poisons
Hypoxia
hypoxia = lack of oxygen
∙ischemia = lack of blood flow
∙ischemia can cause hypoxia
without oxygen, 2 things happen in cell
∙inability to make ATP affects polarization of membrane
∙not having O2 changes us from aerobic metabolism to anaerobic
metabolism
,What is pathophysiology?
not only cellular and organ changes that occur with disease, but with the
effects that these changes have on total body function
Atrophy
decrease in size of tissue organs resulting from a decrease in cell size or in
number of cells
causes include disuse, loss of trophic stimuli (i.e. loss of innervation),
insufficient nutrients, decreased blood flow, persistent cell injury, and aging
cells decrease cellular machinery, decrease oxygen/glucose needs, decrease
number of organelles
Hypertrophy
increase in cell size, and thus an increase in amount of functioning tissue
mass
results from an increased workload imposed on an organ or body part
involves an increase in the functional components of the cell that allows it to
achieve equilibrium b/w demand and functional capacity
,Hyperplasia
increase in number of cells in an organ or tissue
∙can only occur in tissues that are capable of mitotic division
controlled process that occurs in response to an appropriate stimulus and
ceases after stimulus has been removed
more dangerous than hypertrophy → b/c of increased division, increased
risk of cancer
example: prostate, uterus/breast tissue in pregnancy/puberty
Metaplasia
reversible change in which one adult cell type is replaced by another adult
cell type
∙only kind of cell of that is replaced is present, i.e. epithelial cells are
replaced by a different type of epithelial cell
thought to involve the reprogramming of undifferentiated stem cells that are
present in tissue
usually occurs in response to chronic irritation and inflammation which
allows for substitution of cells that are better able to survive
seen in Barrett's esophagus
Dysplasia
, characterized by deranged cell growth of a specific tissue that results in cells
that vary in size, shape and appearance
∙thought of as replacement of mature cell by immature cells, that can
differentiate into different cell types
involves sequential mutations in proliferating cell populations
pattern is most frequently encountered in metaplastic squamous epithelium
of respiratory tract and uterine cervix
strongly implicated as a precursor to cancer
Extremes of Temperature
Heat
∙accelerates cell metabolism
∙inactivates temperature sensitive enzymes (can alter metabolism)
∙disrupts the cell membrane
∙coagulation of blood vessels
∙coagulation of tissue proteins
Cold
∙increases blood viscosity
∙induces vasoconstriction (SNS)
∙ice crystal formation
∙capillary stasis
∙arteriolar and capillary thrombosis
Chemical Agents
similar to poisons that can cause cellular damage
lead causes problems in body b/c unlike a lot of other substances, there is
no threshold of lead that is safe for the body
∙very high levels of lead can cause mental retardation, coma, convulsion and
death
∙low levels of lead can cause reduced IQ and attention span, impaired
PATHOPHYSIOLOGY EXAM
Levels of Cellular Injury
stress causes cell to adapt, but at some point it will eventually cause injury
injuries can lead to cell death, but at some point along cellular pathway, the
injury can be reversible
at some point, the injury becomes irreversible, and the cell will die, either by
apoptosis or necrosis
Stresses: mechanical forces (usually superficial injuries), electrical injuries,
(electricity can carry heat that damages, electrical impulses can change
electrical balance w/in body), nutritional imbalances, biological agents
(viruses/bacteria), poisons
Hypoxia
hypoxia = lack of oxygen
∙ischemia = lack of blood flow
∙ischemia can cause hypoxia
without oxygen, 2 things happen in cell
∙inability to make ATP affects polarization of membrane
∙not having O2 changes us from aerobic metabolism to anaerobic
metabolism
,What is pathophysiology?
not only cellular and organ changes that occur with disease, but with the
effects that these changes have on total body function
Atrophy
decrease in size of tissue organs resulting from a decrease in cell size or in
number of cells
causes include disuse, loss of trophic stimuli (i.e. loss of innervation),
insufficient nutrients, decreased blood flow, persistent cell injury, and aging
cells decrease cellular machinery, decrease oxygen/glucose needs, decrease
number of organelles
Hypertrophy
increase in cell size, and thus an increase in amount of functioning tissue
mass
results from an increased workload imposed on an organ or body part
involves an increase in the functional components of the cell that allows it to
achieve equilibrium b/w demand and functional capacity
,Hyperplasia
increase in number of cells in an organ or tissue
∙can only occur in tissues that are capable of mitotic division
controlled process that occurs in response to an appropriate stimulus and
ceases after stimulus has been removed
more dangerous than hypertrophy → b/c of increased division, increased
risk of cancer
example: prostate, uterus/breast tissue in pregnancy/puberty
Metaplasia
reversible change in which one adult cell type is replaced by another adult
cell type
∙only kind of cell of that is replaced is present, i.e. epithelial cells are
replaced by a different type of epithelial cell
thought to involve the reprogramming of undifferentiated stem cells that are
present in tissue
usually occurs in response to chronic irritation and inflammation which
allows for substitution of cells that are better able to survive
seen in Barrett's esophagus
Dysplasia
, characterized by deranged cell growth of a specific tissue that results in cells
that vary in size, shape and appearance
∙thought of as replacement of mature cell by immature cells, that can
differentiate into different cell types
involves sequential mutations in proliferating cell populations
pattern is most frequently encountered in metaplastic squamous epithelium
of respiratory tract and uterine cervix
strongly implicated as a precursor to cancer
Extremes of Temperature
Heat
∙accelerates cell metabolism
∙inactivates temperature sensitive enzymes (can alter metabolism)
∙disrupts the cell membrane
∙coagulation of blood vessels
∙coagulation of tissue proteins
Cold
∙increases blood viscosity
∙induces vasoconstriction (SNS)
∙ice crystal formation
∙capillary stasis
∙arteriolar and capillary thrombosis
Chemical Agents
similar to poisons that can cause cellular damage
lead causes problems in body b/c unlike a lot of other substances, there is
no threshold of lead that is safe for the body
∙very high levels of lead can cause mental retardation, coma, convulsion and
death
∙low levels of lead can cause reduced IQ and attention span, impaired
