Cell Injury And Fate Flashcards
Why might a cell have to adapt and shift away from being a normal cell/ homeostasis?
Stress, increased demand
What are the two types of cell injury?
Sublethal and lethal
What is lethal cell injury?
one that produces cell death
what is sublethal injury?
Produces injury but not amounting to cell death - may be reversible or even progress to cell death
What are seven causes of cell death?
- Oxygen deprivation
- Chemical agents
- Infectious agents
- Immunological reactions
- Genetic defects
- Nutritional imbalances
- Physical agents eg trauma or rdiation
- Aging
If a cell adapts by increasing load, what does that lead to?
hypertrophy
What can lead to oxygen deprivation, and therefore cell death?
myocardial infarction
The cellular response to injurious stimuli depends on…
- type of injury
- duration
- severity of injury
The consequences of an injurious stimuli depend on?
- Type of cell
- its states (i.e., where it is during mitosis)
Can bone or brain live longer without O2?
Brain
What are 4 intracellular systems which are particularly vulnerable to cell injury?
- Cell membrane integrity
- ATP generation
- Protein synthesis
- Integrity of genetic apparatus
Is cellular function lost before cell death occurs?
Yes, which in turn occurs before the morphological changes are seen
What is meant by atrophy?
Shrinkage in size of a cell / organ by the loss of cell substance eg shrinking brain in dementia patient
What is an example of atrophy of the brain?
Dementia patient- neurones have atrophied
What is meant by hypertrophy?
Increase in the size of the cells and consequently in the size of the organ as well
Is hypertrophy physiological or pathological?
Both
What causes hypertrophy?
it is caused by increased functional demand or specific hormonal stimulation
What is a pathological example of hypertrophy?
‘Pathological’ cardiac hypertrophy is a condition that is characterised by the thickening of the heart muscle, a decrease in the size of the chambers of the heart, and a reduced capacity of the heart to pump blood to the tissues and organs around the body.
What is an example of physiological hypertrophy?
increase in the size of cells of the uterus during pregnancy to accomodate for the foetus
Can muscle fibres proliferate?
No, so they must expand- aka hypertrophy
What is meant by hyperplasia?
An increase in he number of cells in an organ
Is hyperplasia pathological or physiological?
both
What is the main cause of pathological hyperplasia
usually due to excessive hormonal or growth factor stimulation
What can cause physiological hyperplasia?
hormonal I.e., uterus and oestrogen
Compensatory I.e., in the kidney
Describe a physiological example where hyperplasia can occur?
increased oestrogen stimulation drives the increased proliferation of the endometrial glands leading to increased number of endometrial cells