General and Systemic Pathology Flashcards
What are the possible outcomes for a cell that undergoes stress and injurious stimuli
- It can adapt to the stress
- it can become injured
- it can reverse the injury and return to normal
- if the injury is irreversible then the cell will die
What determines if cell injury is reversible or not
how severe and lasting the injury is
What are the two types of cell death
necrosis
apoptosis
What are the reversible changes of a cell ,which things cause ADAPTATION
- atrophy
- hypertrophy
- hyperplasia
- metaplasia
What is atrophy
shrinkage in the size of the cell by loss of cell substance
What can cause atrophy of a cell
- disuse
- inadequate nutrients
- lack of endocrine supply
- poor blood supply
- denervation
- aging
What is involution
a reduced number of cells
what causes involution
- disuse
- inadequate nutrients
- lack of endocrine supply
- poor blood supply
- denervation
- aging
(same things as atrophy)
What happens when you have had atrophy or involution and then the harmful stimulus ends
cellular regrowth back to stable tissue
what is hypertrophy
increased cell size, and thus increased size of the organ
what is hyperplasia
increased number of cells, and thus increased size of the organ
hypertrophy and hyperplasia are caused by the same stimuli, what is that stimuli
- increased work demand
- metabolic demand
- excess endocrine stimulus
- persisting injury
What happens with a cell that has had hypertrophy and hyperplasia after the simulus ends
a reduction in number of cells, or the size of the cells
What is metaplasia
replacement of one cell type by another cell type (usually a less differentiated cell
what is dysplasia
more severe version of metaplasia
what causes metaplasia
persisting injury
What can happen to function of the cell in metaplasia
you can have loss of normal cell functions
What causes dysplasia
persistent SEVERE injury or irritation
How do you recognize dysplasia when compaired to metaplasia
dysplasia will have many more cells, more replacement of cells
What determines how much fat your body stores? how many adipocytes you have, or the size of your adipocytes
the size of your adipocytes
What determines your bodies ability to store fat
- gestatinal birth weight
- maternal insulin
- in utero toxin exposure
Normally adipocytes undergo hypertrophy, can they also under hyperplasia
yes when adults have hit 170% of their body weight
What are the 10 causes of cellular INJURY
- oxygen deprivation
- chemical agents
- infectious agents
- immunologic reactions
- genetic factors
- nutritional imbalances
- physical agents
- radiation
- calcium
- aging
What is the most common cause of cellular injury
oxygen deprivation
what is ischemia
the lack of oxygen in a cell or tissue due to lack of blood flow to it
What is hypoxia
low oxygen to the cell
what is anoxia
no oxygen to the cell
What causes ischemia
hypoxia and anoxia
how does oxygen depletion or ischemia lead to cellular damage
- low O2 leads to low ATP
- low ATP leads to sodium-potassium pump, and calcium pump failing
- the imbalance of ions (Na. K. and Ca) cause water to enter the cell, and the cell to swell
- if this isn’t fixed then the cell will lyse
What is reperfusion injury
injury that occurs with rapid restoration of blood to ischemic tissues.
how does rapid restoration of blood to ischemic tissues lead to a reperfusion injury
the mitochondria has adapted to not having Oxygen, so when Oxygen is reintroduced the mitochondria Reactive Oxygen species are created by the unused electrons in the ETS
What can these Reactive oxygen Species do in the body
- lipid peroxidation
- alterations of proteins
- alteration of DNA
What is the product when unused electrons from the ETS react with O2 in reperfusion injuries
O2 and the electrons make H2O2.
What can then happen with the H2O2 that is caused by the joining of Electrons and O2
- it can be neutralized by catalase
- it can be neutralized by glutathione
- if not neutralized it becomes OH radical (harmful Reactive Oxygen Species)
What happens to the mitochondria in hypopoxia
the mitochondria will swell
