cell injury/death Flashcards
what is atrophy, and what happens
- decrease in cell size
- reduced consumption of oxygen and other cell functions by decreasing the number and size of organelles
- lower level of functioning
5 causes of atrophy
- disuse
- denervation
- loss of endocrine stimulation
- inadequate nutrition
- ischemia
what is hypertrophy and why does it occur
- increase cell size
- increased workload imposed by an organ/body part
what are the 2 types of hypertrophy
- normal physiological (increased muscle mass with exercise)
- abnormal pathologic (thickening of urinary bladder from long term obstruction of urine outflow)
what is compensatory hypertrophy
ex. one kidney is removed and the other enlarges to compensate
what is hyperplasia
an increased number of cells
what are the 2 types of hyperplasia
- hormonal (breast and uterine enlargement during pregnancy)
- compensatory (regeneration of the liver after partial removal)
what is hyperplasia vital for
wound healing
what is metaplasia
replacing one cell type with another cell type
what does metaplasia occur in response to
chronic irritation and inflammation
what is dysplasia
disorganization of cells
what does dysplasia look like
varied cell size, shape, and organization
what is dysplasia associated with
cancer
what is anaplasia
an advanced form of dysplasia
the 3 mechanisms of cell injury
- free radical production
- hypoxic cell injury
- impaired calcium homeostasis
what are free radicals
- reactive, unstable, toxic chemicals
- have an odd, unpaired outer electron
what is oxidization
stealing an electron from the closest molecule in order to become stable, which causes that molecule to become a free radical
what do antioxidants do
counteract oxidization by donating electrons
what is oxidative stress
when the generation of free radicals exceeds the ability of the body to neutralize or eliminate them
what does oxidative stress likely play a role in
cancer development
what is ATP
energy for cells
what does hypoxia do to cells
deprives the cell of oxygen and interrupts oxidative metabolism and the generation of ATP
what is required for ATP production
oxygen, for aerobic cellular respiration
how many ATP molecules does aerobic cellular respiration yield
34