17 Cellular adaptation Flashcards
What do cell adaptations involve changes in? (5).
Size. Number. Phenotype. Metabolic activity. Function.
Which cell type can adapt easily to a change in environment?
Labile cells.
Which cell type cannot adapt to changes in environment?
Terminally differentiated cells.
What is the difference between physiological and pathological cell adaptation?
Responding to physiological changes vs disease related changes.
Differentiate between hypertrophy and hyperplasia:
Hypertrophy: increased size.
Hyperplasia: increased numbers.
Give two examples of physiological hypertrophy:
Uterus in pregnancy.
Adenomatous hyperplasia of prostate.
Which type of cell population is hypertrophy particularly seen in?
Permanent cell populations e.g. skeletal of cardiac muscle.
What is sub cellular hypertrophy/hyperplasia?
Increase in size/number of organelles within a cell.
Give an example of sub cellular hypertrophy
Barbiturates cause hypertrophy or smooth ER, increasing the metabolism of other drugs.
Give two examples of hyperplasia (not cancerous):
Gynaecomastia.
Compensatory hyperplasia of kidney in response to contralateral hypoplasia.
Define atrophy:
Reduction in size of organ/tissue due to decrease in cell size or number.
Give two examples of physiological atrophy:
Embryogenesis.
Uterus after pregnancy/menopause.
What are the reasons for pathological atrophy? (6).
Decreased workload. Loss of innervation. Decreased blood supply. Inadequate nutrition. Loss of endocrine function. Pressure.
What is involution?
Physiological atrophy by apoptosis.
What is agenesis?
Failure of embryonic cell mass formation.
What is aplasia?
Failure of differentiation into organ specific tissue.
What is dysgenesis?
Failure of structural organisation of tissues into an organ.
Define metaplasia:
Transformation of one differentiated cell type into another.
Give an example of physiological metaplasia/
Moving of squamo-columnar junction in cervix during puberty and menopause.
What causes metaplasia of transitional bladder epithelium to squamous epithelium? (3).
Bladder calculus.
Schistosomiasis.
Longstanding catheter.
What causes metaplasia of fibrocollagenous tissue into bone?
Chronic trauma.
What is dysplasia?
Earliest morphological manifestation of neoplasia.
Irreversible but non-invasive.
Showes cytological features of malignancy.
