Quiz 1 Flashcards
Small dense nucleus, first stage of cell death
Pyknosis
fragmentation, second stage of cell death
Karyorrhexis
dissolution of nucleus by lysosomal enzymes, third stage of cell death
Karyolysis
death of a group of cells in the living body
necrosis
proteins become hard
denaturation
cell becomes liquified
liquifactive necrosis
most common type of necrosis
Coagulative
Coagulative necrosis is mostly caused by?
Lack of oxygen
Coagulative necrosis occurs where?
all tissue except brain and abscesses
Coagulative necrosis results a cell that is:
pale, firm and swollen
Mechanism of Colliquitive (Liquifactive) Necrosis
Cell Lysis, prevail over protein denaturation
Causes of Liquificative Necrosis
Necrotic Lesions of the brain, suppurative inflammation (abscess, has puss): puss attracts proteolytic enzymes of neutrophils
What is the cause of Caseous Necrosis?
TB (Tuberculosis)
What does Caseous Necrosis look like?
white and cheesy, debris appears soft and friable (easily separates like bread crumbs)
What is the shape of a cell undergoing Caseous Necrosis?
Amorphous (Shapeless)
Enzymatic Fat Necrosis is caused by?
Release of pancreatic enzymes into surrounding tissue (pancreatitis)
Mechanism of Enzymatic Fat Necrosis:
Phospholipases attack plasma membrane
What is the appearance of Enzymatic Fat Necrosis?
Chalky white, caused by amino acids and
Traumatic Fat Necrosis is caused by?
Trauma (not enzymatic digestion) to fatty tissue
Mechanism of Traumatic Fat Necrosis:
Release of intracellular fat —> acute
inflammation and fibrosis —> firm mass mistaken for breast cancer
Fibrinoid Necrosis occurs where?
blood vessels (in tunica media)
Causes of Fibrinoid Necrosis:
Malignant Hypertension, Autoimmune Diseases: Rheumatoid Arthritis
Mass necrosis of tissue due to vascular occlusion followed by putrefaction
Gangrene
- Occurs in TOES and FEET due to occlusion of arteries due to DIABETES —>(COAGULATIVE NECROSIS)
- Necrotic tissue is dry, shrunken, mummified and black
- Bacterial Infection: minimal
- LINE OF DEMARCATION between gangrenous area and adjacent living tissue
Dry Gangrene
- Occurs in limbs (crush injury), internal organs (intestinal strangulation) —> occlusion of both artery and vein
- Necrotic tissue swollen, moist and black
- Severe bacterial infection, liquifaction of dead tissue and toxemia (LIQUIFACTIVE NECROSIS)
Wet Gangrene
- Both tissue necrosis and putrification are caused by BACTERIA
- Due to contamination of DEEP WOUNDS involving muscles with CLOSTRIDIUM PERFRINGENS
- palpation of tissue produces CRACKLING SENSATION (CO2 and H2S)
Gas Gangrene
Death of single cells within a cluster of living cells
Apoptosis
The following are features of what?
Cell shrinkage, apoptotic bodies (fragmentation of cell), surface blebs from membrane
In apoptosis, cell fragments are eaten by:
Phagocytes
Physiological Causes of Apoptoss:
- lumina in hollow organs during embryogenesis
- Involution of thymus in adults
- deletion of self reactive lymphocytes in thymus
Pathological Causes of Apoptosis:
- Cell Injury in Viral Hepatitis —> apoptotic bodies (known as COUNCILMAN BODIES)
