2.2 MoD Tumours & Cancer Flashcards
(116 cards)
Reversible cellular changes in response to changes in the environment or demand.
Adaptation
Give 4 ways a cell can adapt.
- Size
- Number
- Phenotype
- Metabolic activity
- Function
How susceptible to adaptation are fibroblasts?
Do NOT need to adapt.
They can withstand a lot of metabolic stress
e.g. hypoxia
How susceptible to adaptation are epithelial cells?
Adapt very easily.
Labile cell population which are constantly under different types of stress so need to be able to adapt.
How susceptible to adaptation are cerebral neurons?
Cannot adapt.
Terminally differentiated permanent cell population.
Highly specialised and sensitive cells which cannot adapt to change.
What is the difference between physiological and pathological cellular adaptation?
Are they mutually exclusive?
Physiological = responding to normal changes in physiology or demand (slight fluctuations to what we’re used to).
Pathological = responding to disease causing change.
No, if a physiological change is excessive or prolonged, it can become pathological and harm the cell.
How would a cell respond to increased cellular activity?
Increase in size + number.
opposite if there is decreased cellular activity
Define hypertrophy.
Increase in size of cell.
Define hyperplasia.
Increase in the number of cells.
Which cell population is hypertrophy very common in? Give an example.
Permanent cell populations.
e.g. cardiac muscle + skeletal muscle.
How does the myocardium respond/adapt to an aortic stenosis?
Hypertrophy of the heart muscle.
has to work harder due to the narrowing/stiffening of the valve
What problems (symptoms) are associated with LVH (left ventricular hypertrophy)?
How would you diagnose?
Shortness of breath fatigue chest pain worse after exercise heart fluttering/palpitations dizziness
displaced apex beat
irregular heart rhythm
x-ray = prominent heart outline
ECG = bigger peaks, S waves which shouldn’t be there, echocardiogram = thickened heart muscle. Due to exercise?
Barbiturates (sleeping pills/psychiatric drugs) can cause hypertrophy in what?
Endoplasmic reticulum of hepatocytes (subcellular hypertrophy).
Increased demand of P450 enzymes to metabolise the drug leads to hypertrophy of the SER to produce more.
(alcohol consumption also increases demand for P450 enzymes)
Is hyperplasia of the liver after donation of a liver segment physiological or pathological?
Physiological - compensatory
Is Grave’s disease a result of hypertrophy or hyperplasia?
Hyperplasia of thyroid
Define atrophy.
Reduction in size of an organ/tissue by a decrease in the size and number of cells.
Reduction in size of tissue during embryogenesis, uterus after pregnancy or menopause are examples of what?
Involution - physiological atrophy
Give 4 examples of what can cause atrophy.
- Decreased workload (disuse atrophy)
- Loss of innervation (denervation atrophy)
- Diminished blood supply
- Inadequate nutrition
- Loss of endocrine stimulation
- Pressure
What can renal artery stenosis cause?
Atrophy of the kidney due to a decreased blood supply.
The thymus undergoes physiological hypertrophy as you get older.
True or False?
FALSE
thymus gets smaller (physiological ATROPHY) because you don’t need it as much when your older
Why is it important in a patient chronically taking steroids, that you ease them off the medication rather than just stopping it all together?
Your adrenal glands undergo atrophy due to chronic steroid therapy which reduces ACTH drive (stimulates adrenals to secrete glucocorticoids).
If you suddenly stop steroid medication, your adrenals cannot cope and produce enough steroids which is very dangerous.
What is the most common cause of LVH?
Hypertension
A horseshoe kidney is an example of?
Aplasia
Agenesis
Dysgenesis
Hypoplasia
Dysgenesis - failure of the tissues to organise themselves into the correct organ structure.
Failure of an organ to grow to full size
Hypoplasia