Cellular Adaptations Flashcards
Cellular adaptations?
- cells adapt to changes in workload and adverse conditions
- short term (usually)
- In diseases, cellular adaptations are long term.
List an example of a short term cellular adaptation.
Increased demand on heart from exercise, need more O2 and blood supply so HR increases.
Atrophy?
Decrease in size (d/t decreased workload & adverse environment) of cell or decrease in number of cells.
What are some attributes of atrophy?
- Lower level of functioning (minimal resource supply, inadequate perfusion)
- Decrease in tissue mass & function [d/t decrease in size and/or number of cells.
What would you do when cells can’t replicate?
You would decrease the size (atrophy)
Hyperplasia?
Increase in number of cells.
What are some attributes of hyperplasia?
- Higher level of functioning
- Increase in tissue mass
- compensatory or pathologic
- muscle cell DO NOT do this (muscle cells do not multiply) *
- can replicate*
Can hyperplasia occur in muscle cells? Why or why not?
No, because muscle cells do not multiply.
Hypertrophy?
Increase in cell size and function.
What are some attributes of hypertrophy?
- higher level of functioning (d/t the increase in cell size, mass and workload)
- increase in tissue mass
- CAN be compensatory or pathologic
- CAN’T replicate *
Can hypertrophy replicate?
NO
What is the difference between hyperplasia and hypertrophy?
- Hyperplasia is an increase in the NUMBER of cells and can replicate where as hypertrophy is in an increase in the cell SIZE and cannot replicate.
Can hyperplasia replicate?
Yes
Metaplasia?
Replacing 1 tissue/cell type with another tissue/cell type. (both are normal except the replacing tissue doesn’t belong in that area of the body)
What are some attributes of metaplasia?
- adaptive change not pathologic
- occurs after an area is persistently irritated d/t chronic irritation and inflammation
List an example of metaplasia occurring.
Smoking irritates the lining of the respiratory tract, creates new tissue.
- pseudostratified ciliated columnar have goblet cells that secrete mucus and cilia that beat in the opposite direction of the throat so mucus is spit up (the Muco-ciliary blanket).
- Smoking irritates the cells and deeper layers
- metaplasia replaces this single-layer tissue with several-layered tissues
- this new tissue (stratified squamous) does not have cilia to beat away secretions, which causes problems (‘smokers cough’)
What is a result of the following example of metaplasia.
- If gastric acid damage occurs in the digestive tract and single layer cells are replaced with multi-layered cells that lack villi.
Then absorption is decreased.
Dysplasia?
Tissue with abnormal cell size, shape and organization (disorganization of the tissue)
What are some of the attributes of dysplasia?
- cells divide and differentiate (change shape)
- Normal division but abnormal differentiation
- varied cell size, shape and organization
- warning sign for abnormal changes (often pre-cancerous) [known as the precursor of cancer]
Anaplasia?
Advanced form of dysplasia
What are some of the attributes of anaplasia?
- undifferentiated cells (can’t do normal function)
- variable structure
- associated with cancer
Why does cell death occur?
- the body creates a balance between forming and removing cells
- some cells die after a certain amount of time or a certain amount of divisions
- cell death is NORMAL (body needs to replace old cells)
Necrosis?
Cell death due to injury
What are some of the attributes of necrosis?
- it is cell death in an organ or tissue that is still part of a living organism
- Abnormal / not expected
- interferes with cell replacement and tissue regeneration
- triggers the inflammatory process
