Histopathology Flashcards
Cell that frequently divide to replace lost cells
Labile cells
not typically dividing to replace injured cells
Do not frequently go cell division
Only undergo replication to replace injured cells
Stable cells
Stable cells examples
Parenchymal cells of liver and kidneys
Cell class that do not undergo replication following maturation
Permanent Cell
Permanent cell example
neurons (nerve cell)
incomplete or defective development of tissue/organ. Shows no resemblance to the normal mature structure. Usually happens in paired organs (kidneys, gonads)
Aplasia
complete non-appearance of organ.
Agenesia
failure of tissue/organ to reach normal mature adult size
Hypoplasia
Failure of organ to form an opening
Example:
Imperforate anus (without opening)
Microtia - absence of ear canal
Atresia
Cellular adaptation mechanisms
Atrohpy
Hypertrophy
Hyperplasia
Metaplasia
Dysplasia
Anaplasia
acquired decrease in tissue or organ size
Atrophy
Atrophy that occurs as consequence of maturation
example:
Atrophy of thymus at puberty
Decrease in uterus size after childbirth
Physiologic
Pathologic atrophy:
occurs if blood supply becomes reduced or below the critical level (may develop as a result of pressure atrophy)
Vascular atrophy
Pathologic atrophy:
persistent pressure on the organ or tissue may directly injure the cell or may secondarily promote diminution of blood supply
Pressure atrophy
Pathology atrophy:
due to lack of hormones needed to maintain normal size and structure
Endocrine atrophy
Pathologic atrophy:
due to lack of nutritional supply to sustain normal growth
Hunger/Starvation atrophy
Pathologic atrophy:
too much workload can cause general wasting of tissues
Exhaustion atrophy
Pathologic atrophy:
Inactivity/diminished activity/functions
Atrophy of disuse
Increase in tissue/organ size due to an increase in size of cells making up the organ
Hypertrophy
hypertrophy of skeletal muscles due to frequent exercise
Physiologic hypertrophy
Hypertrophy of the myocardium (hypertension)
Aortic valve disease
Pathologic hypertrophy
Type of hypertrophy that may develop as response to a deficiency (usually in paired organs– when one is removed)
Compensatory
Example of compensatory hyperthrophy
Renal hypertrophy
Increase in tissue or organ size due to an increase in the number of the cells making up the organ (new cells are formed)
Hyperplasia