D&D Unit 1-2 Flashcards
(230 cards)
Human disease occurs mostly from injury to the _________
Epithelium
What is metaplasia?
A reversible change in which one adult cell type is replaced by another cel type
5 types of necrosis
Coagulative Liquefactive Caseous Fat Fibrinoid
What is coagulative necrosis?
Tissue architecture is preserved for at least several days before they are digested
What is liquefactive necrosis?
Usually in infections where leukocyte enzyme digest tissue Also forms in hypoxic death of CNS cells
What is caseous necrosis?
Looks chalky white- like casein (milk) Central portion of an infection is necrotic (fragmented or lysed cells) and inflamed on borders
When does fat necrosis occur?
From release of pancreatic lipases Or from trauma to fat areas
4 reversible changes that occur in hypoxia
Decreased ATP
Decrease Na pump -> swelling
Increased glycolysis -> decreased pH
Decreased protein synthesis
3 irreversible changes that occur in hypoxia
Activation of lysosomal enzymes
DNA and protein degradation
Ca2+ influx
4 big picture cellular adaptations to stress
Hypertrophy
Hyperplasia
Atrophy
Metaplasia
Metaplasia nomenclature
Metaplasia is named for whatever tissue replaces normal tissue
Why does fat accumulate in injured cells as lipid vacuoles in the cytoplasm?
Increased entry and synthesis of free fatty acids Decreased fatty acid oxidation
4 intracellular changes associated with reversible cell injury
Plasma membrane alterations (blebbing, blunting, distortion, loosening of intercellular attachments)
Mitochondrial changes (swelling and appearance of phospholipid-rich amorphous densities)
Dilation of ER with detachment of ribosomes and dissociation of polyribosomes
Nuclear alterations with chromatin clumping
Describe pyknosis
Nuclear shrinkage and increased basophilia (chromatin condenses) Step 1
Describe karyorrhexis
The pyknotic nucleus fragments Step 2
Describe karyolysis
The nucleus dissolves Step 3
What type of necrosis is gangrene?
A coagulative necrosis involving multiple tissue layers
What is fibrinoid necrosis?
An immune reaction in which complexes of antigens and antibodies are deposited in walls of arteries and combine with fibrin
How does ischemia cause mitochondrial damage and dysfunction?
Failure of oxidative phosphorylation causes:
ATP depletion
Formation of ROS
Formation of pores and loss of membrane potential
Release of proteins that activate apoptosis
Changes to intracelluar calcium in cellular damage
Release of calcium stores from inside
Increased influx accross plasma membrane
2 ways reactive oxygen species accumulate in cellular damage
Mitochondria
Phagocytes
3 important sites of cellular membrane damage
Mitochondria
Plasma membrane
Lysosome
The intrinsic apoptotic pathway is mediated by ________
Mitochondria
The extrinsic apoptotic pathway is mediated by ________
Death receptor