Alterations Of Cell Function Flashcards
Atrophy
A decrease in cellular size
Causes and examples of atrophy
Disuse
Decreased hormonal or nervous stimulation
Ischemia leading to cell hypoxia
Hypertrophy
Increased workload
Bigger cells not more
Example of hypertrophy
Heart failure caused by hypertrophy
Too big to contract
Hypertrophy causes Increased hormonal stimulation in….
Pregnancy causes hypertrophy in uterus and in the mammoth glands
Hypertrophy Patho
Increased mitochondria, actin, myosin
No increase in H2O
More ATP
Hyperplasia
Increase in cell number
Compensatory hyperplasia
Allows organ regeneration
Tissue replacement
An example is the replacement of cells in liver (70%)
Hormonal replacement
Estrogen-dependent organs
Ex) uterus
Pathological hyperplasia
Proliferation of normal cells due to excessive hormone stimulation
Ex) BPH (enlarged prostate) with more testosterone and obstructs urethra
Metaplasia
Prolonged insult (smoking) Ciliated epithelium--> bronchial metaplasia
Dysplasia
Changes in size, shape, and organization
Can be cancerous
DNA mutations
Ex) Cervical dysplasia (HPV)
Hypoxic injury
Lack of O2 in tissues
Hypoxemia
Decrease in O2 content in blood
Ex) asthma, or a high altitude
Anemia
Low hemoglobin count
Ex)RBC lysis
Ischemia
Low blood flow to tissue
Ex) blood clot
Decreased O2--> Anaerobic metabolism--> Decreased ATP--> Na/k pump failure--> Increase of Na in--> Cell swelling
Na plus inside cell
Decrease in O2–> anaerobic metabolism–> decrease in ATP production–> Ca pump failure–> accumulation of Ca–>crystals in mitochondria and damage to plasma membrane
Crystals and damage to plasma membrane
Decrease in O2–> anaerobic–> lactic acid–> decrease in PH in cytoplasm–> lysosomal breakdown–> release of hydrologic enzymes–> autodigestion of cell
Autodigestion of cell
Ryperfusion injury
Introduction of O2 to hypoxic tissue releasing free radicals
Free radicals
Hypoxic cells release xanthine that reacts with O2 to produce free radicals
Has an unpaired e-
Causes of free radicals
Radiation
ATP production (excess exercise)
Inflammation (WBC death)
Chemicals/drugs