Cell Injury (Slides 1-46) Flashcards
Define homeostasis.
Maintaining a steady state
Define atrophy.
Decrease in size and function
Define hypertrophy.
Increase in size
Define hyperplasia.
Increase in number of cells
Define metaplasia.
Change from one cell type to another
What is an example of physiological atrophy?
Involution of the thymus (Shrinking of the thymus from childhood to adulthood)
When does the ubiquitin-proteasome pathway of atrophy begin?
During times of starvation
What happens in the ubiquitin-proteasome pathway?
Decrease protein synthesis
Increased protein degradation
What is autophagy?
“self-eating”
Why would a cell go through the autophagy pathway of cellular atrophy?
Structural proteins and organelles are destroyed to reduce the cell’s metabolic overhead
What is lipofuscin?
Autophagic vacuoles that may resist digestion and persist as membrane bound residual bodies that may remain as a sarcophagus in the cytoplasm
What is an example of pathologic atrophy?
When legs are immobilized for an extended period of time
Senile atrophy of the brain
What are some reasons that physiological hypertrophy happen?
Increased workload (body builders) Hormone induced (uterus and breasts)
What is the only kind of cardiac hypertrophy that does not affect lumen size?
Physiological hypertrophy
How does pathological cardiac hypertrophy affect lumen size?
Reduces it
