Week 1 Flashcards
nName some causes of cell injury?
-Oxygen deprivation (Hypoxia)
- Chemicals
-Enzymes
- Infectious agents
- Immunological reactions
- Genetic defects
- Nutritional imbalances
- Trauma
What are free radicals?
- Single unpaired electron
- Unstable
- Very reactive > chain reaction
What can you do to remove free radicals?
- Electron donation
- Antioxidant
Removing free radicals pathway
What is atrophy and example?
Decrease in size or wasting away of a body part or tissue
Examples:
- Muscle atrophy
- Atrophy of optic nerve = dimishes vision
- Cerebral atrophy = alzheimers disease, ageing, alcohol
What are the effects of alcohol on brain?
Effects of alcohol on a developing brain
-Sensitive to alcohol abuse
- Lower oxygen consumption
- Functional loss > atrophy and irreversible cell loss if continued.
What is the cellular basis of atrophy?
Two proteolytic systems:
- Lysosomes
- organelles that contain
proteases(proteins), lipases (lipids),
glycosides (sugars/ carbohydrate)
- Ubiquitin pathway
- Involves digestion in proteosomes
- Atrophy may be accompanied by increase in autophagic vesicles ( a fusion of lysosomes with intracellular organelles)
What is the role of lysosomes?
Fuses with vacuoles that contain material destined for recycling
Broken down in two ways: Heterophagy and autophagy
What is heterophagy?
- process of a cell consuming material from its environment
What is autophagy?
Cytoplasm or damaged organelles enclosed in autophagosome
Tay-Sachs disease
-8 months; blind and muscle rigidity
-Cannot stand or sit at appropriate age
-Deterioration of nervous system
- Death at 4 years
- Lipid accumulation(gangliosides) in nerve cells (normally made and degraded rapidly as brain develops)
What is hypertophy?
An enlargment or overgrowth of part of the body due to increase size of the constituent cells
- Increase in size of cells
