Cellular adaptations and cell death Flashcards
What are the 3 proliferative capacities of cells?
Permanent (non-proliferative)
Stable (non-proliferative but capable if required)
Labile (proliferative)
What is hypertrophy?
Increase in cell size due to gain of cellular substance
Hypertrophy typically occurs in cells with which proliferative capacity?
Permanent
What are the 2 main mechanisms which lead to hypertrophy?
Increased functional demand
Hormonal stimulation
Enlargement of the uterus during pregnancy is an example of which type of cellular adaptation?
Physiological hypertrophy due to hormonal stimulation
What is the proliferative capacity of skeletal muscle cells?
Permanent
What is hyperplasia?
Increase in cell number
What are the 2 types of physiological hyperplasia?
Hormonal hyperplasia
Compensatory hyperplasia
What is atrophy?
Reduction in cell size due to loss of cellular substance
List 6 causes of cellular atrophy.
- Decreased workload
- Loss of innervation
- Diminished blood supply
- Inadequate nutrition
- Loss of endocrine stimulation
- Ageing
What is metaplasia?
One adult cell type is replaced by another adult cell type
What is dysplasia?
Abnormal development of cells within a tissue or organ
What are the 3 features of dysplasia?
Nuclear enlargement
Loss of nuclear polarity
Increased cell division
Why is ischaemia worse than hypoxia?
It involves both lack of oxygen and nutrient deprivation, and build up of toxins
What are free radicals?
Atoms with unpaired electrons, which makes them highly reactive and chemically unstable
What is a re-perfusion injury?
When blood supply is restored, it causes a burst of mitochondrial activity, which causes excessive release of free radicals, leading to tissue damage
Name 2 direct acting toxins.
Mercury
Diphtheria toxin
Name 2 latent acting toxins.
Carbon tetrachloride
Acetaminophen
How does the cell membrane differ in apoptosis vs necrosis?
Apoptosis - membrane integrity retained
Necrosis - membrane integrity lost
Describe the inflammatory response in apoptosis vs necrosis.
Apoptosis - no inflammatory response
Necrosis - inflammatory response
List the 6 types of necrosis.
Coagulative
Liquefactive
Gangrenous
Caseous
Fat
Fibrinoid
Infarcts in the body generally cause which type of necrosis?
Coagulative necrosis
Bacterial infections generally cause which type of necrosis?
Liquefactive necrosis
Which type of necrosis is seen in TB infections?
Caseous necrosis
