Cell injury, cell death and Adaptations.
• Our bodies consist of the basic unit of life, which is called the cell, which
contains within it many organelles that mainly help to carry out various
functions.
a) Cell membrane surrounds all the cells
which is mainly consists of
phospholipids and a lot of proteins.
b) Cytoplasm which has many
organelles such as golgi apparatus ,
ER and mitochondria (energy factory
of cells).
• Cells interact with each other in their
environment to adapt and maintain their function and structure in the event
of stress and demands in their environment.
• We can say that a cell is in a “homeostasis” when the intracellular
components are within a normal range (highly regulated).
…………………………………………………………………………………………………………………………….
• When a cell encounters in any increasing demand or increasing physiological
stress or exposed to a highly injurious stimuli normally the cell will go under
many changes.
• As a result of exposure to these changes, the cell must behave in two
pathways, the first of which is adaptation, which has a certain limit. If it is
exceeded, the cell enters the other pathway, which is cell injury.
• It can be first reversible injury. But if the stress or the injurious stimuli is very
severe, constant progressive or very rapid, the cell will undergo irreversible
injury or what we call cell death.
.............................................................................................................................
What do we mean by reversible and irreversible injuries ?
Reversible injury: cell can return back to its normal conditions after the harmful
stimuli is gone.
Irreversible injury: cell cannot return to the homeostasis state again after the
harmful stimuli is gone.
, Why we study cell injury?
Because cell injury is crucial and basic element in any disease process. All diseases in
the body will start at first by cell injury. So, we have to study cell injury and the
reaction of cells with its surrounding environment whether by first adaptation,
second by reversible cell injury, third by irreversible cell injury or what we call it cell
death.
…………………………………………………………………………………………………………………………………..
Adaptation
Physiological adaptation: phenomena which can be
response for any physiologic stimulation.
Ppathologic adaptation: can be caused by a process of
a disease.
…………………………………………………………………………………………………………………………………..
These forms of cells adaptations are presented in
increase in number which the cells are still alive and functional. But it is
increase in cell size possible for the functions of the cell to change
of cells
according to the type of adaptation that it
forms of undergoes, but whether the functions of the cell
changes or not, it stills alive and functional.
adaptation
Note: in reversible injury the cell stops functioning
change into another until the stress is gone , while in adaptation the cell
decrease in cell size
type of cells stills functional under stress.
• Our bodies consist of the basic unit of life, which is called the cell, which
contains within it many organelles that mainly help to carry out various
functions.
a) Cell membrane surrounds all the cells
which is mainly consists of
phospholipids and a lot of proteins.
b) Cytoplasm which has many
organelles such as golgi apparatus ,
ER and mitochondria (energy factory
of cells).
• Cells interact with each other in their
environment to adapt and maintain their function and structure in the event
of stress and demands in their environment.
• We can say that a cell is in a “homeostasis” when the intracellular
components are within a normal range (highly regulated).
…………………………………………………………………………………………………………………………….
• When a cell encounters in any increasing demand or increasing physiological
stress or exposed to a highly injurious stimuli normally the cell will go under
many changes.
• As a result of exposure to these changes, the cell must behave in two
pathways, the first of which is adaptation, which has a certain limit. If it is
exceeded, the cell enters the other pathway, which is cell injury.
• It can be first reversible injury. But if the stress or the injurious stimuli is very
severe, constant progressive or very rapid, the cell will undergo irreversible
injury or what we call cell death.
.............................................................................................................................
What do we mean by reversible and irreversible injuries ?
Reversible injury: cell can return back to its normal conditions after the harmful
stimuli is gone.
Irreversible injury: cell cannot return to the homeostasis state again after the
harmful stimuli is gone.
, Why we study cell injury?
Because cell injury is crucial and basic element in any disease process. All diseases in
the body will start at first by cell injury. So, we have to study cell injury and the
reaction of cells with its surrounding environment whether by first adaptation,
second by reversible cell injury, third by irreversible cell injury or what we call it cell
death.
…………………………………………………………………………………………………………………………………..
Adaptation
Physiological adaptation: phenomena which can be
response for any physiologic stimulation.
Ppathologic adaptation: can be caused by a process of
a disease.
…………………………………………………………………………………………………………………………………..
These forms of cells adaptations are presented in
increase in number which the cells are still alive and functional. But it is
increase in cell size possible for the functions of the cell to change
of cells
according to the type of adaptation that it
forms of undergoes, but whether the functions of the cell
changes or not, it stills alive and functional.
adaptation
Note: in reversible injury the cell stops functioning
change into another until the stress is gone , while in adaptation the cell
decrease in cell size
type of cells stills functional under stress.
