Cell Injury Flashcards
What are the two forms of endoplasmic reticulum?
Rough ER - with ribosomes and synthesizes proteins to be exported from the cell
Smooth ER - without ribosomes and metabolizes drugs hormones and various nutrients, synthesizes steroid hormones
What is the plasma membrane?
A structural barrier between cell and external environment that communicates with other cells
What is the plasma membrane made of?
Proteins, lipids, carbohydrates, and it is a bi layers with lipids on each side
What are the three primary tissue layers?
Endoderm, ectoderm, mesoderm
What are the two types of cells?
Epithelium and mesnechyma
What is an example of epithelium?
Skin or lining of vessels, ducts, and other small cavities
What does epithelium consist of?
Cells joined by cementing substances
How is epithelium classified?
Number of layers and the shape of cells
What does mesenchyma form?
Bone, muscle, fat, cartilage, and fibrous tissue
Parenchyma vs stoma?
Parenchyma is the working elements of tissue types and usually consists of epithelial cells
Stroke is the structural support and framework of an organ, usually made by mesenchyma
Define the “steady state”
A balance between opposing pressures operating in or around cell or tissue
What can alter the steady state?
Normal- physiologic changes
Abnormal - pathological changes
Altered steady state?
Returns to the steady state quickly
Cellular adaptation?
A permanent change to steady state
Example: menopause, the lower estrogen signals to stop shedding uterine lining
Reversible cell injury
Cell can reverse the damages before too much occurs and results in permanent damage
Example: blood clot or increased troponin levels during a heart attack
Irreversible cell injury causes?
Heavy doses of toxins, sever hypoxia or anoxia, other prolonged insults
When does cellular adaptation occur?
When there is persistent and prolonged changes
Atrophy definition
Means without nutrition, there’s a decrease in size of individual cells
Causes of atrophy?
Less oxygen, less nutrition ,stimulation
The cells are trying to survive and requires a decrease in activity
Looks smaller than normal
Microscopically the cells look much smaller compared to normal cells
What cellular adaptation causes carpal tunnel?
Atrophy
Hypertrophy definition
Increase in size of cells in response to functional demands
IE: skeletal or cardiac number
Cells appear much bigger microscopically
Left ventricular hypertrophy
Is thickening of the septum in the heart
Hyperplasia
Increase in NUMBER of cells due to increase functional demand
Cells will divide to do so
Typically caused by hormonal stimulation
What cellular adaptation causes thyroid goiter ?
Hyperplasia
Hypoplasia definition
Underdevelopment of an organ or tissue
Example: failure of kidney to develop to normal adult size
Aplasia
Failure of an organ or tissue to develop
Example: kidney fails to ever form
Metaplasia
Substitution of one cell type for another
What causes metaplasia?
Harsh environments inducing change to protective tissue type
What type of cellular adaptation would cause a smokers lung cells to switch from stratified squamous cells to ciliated columnar cells?
Metaplasia
Dysplasia
Abnormal growth of cells that is potentially reversible
What are the five cellular accumulations?
Water, lipids, carbs, proteins, pigment
Examples of pigments in cellular accumulation
Smog can cause pigment on lungs
Exogenous pigments examples
Occurring from the outside -
Environmental contamination like smog
Tattoo ink
Amalgam from dental work
Endogenous pigments
Occurs from inside -
Lipofuscin
Melanin
Iron
Bilirubin
What is the wear and tear pigment?
Lipofuscin
Usually looks brown and occurs in older patients
Does not interfere with cell function
What is hemochromatosis
Accumulation of too much iron throughout the body that is an inhertited gene
What is pyknosis?
A type of cell death where the cells condenses
What is karyorrhexis?
A type of cell death where the nucleus fragments
What is karyolysis?
A type of cell death where the nucleus dissolutes and has lysis of chromatin
What are the two types of cell death?
Apoptosis and necrosis
Which type of cell death is “active” and energy dependent
Apoptosis
Which type of cell death is “active” and energy dependent
Apoptosis
Which form of cell death causes inflammation and damage to surrounding cells
Necrosis
Which form of cell death causes inflammation and damage to surrounding cells
Necrosis
How is necrosis cell death initiated?
Exogenous cell injury and is always pathologic
Does not depend on energy
Which type of necrosis turns cells into liquid?
Liquefactive
Which type of necrosis is associated with infectious diseases?
Caseous necrosis
What are the causes of metabolic injury ?
Hypoxia and anoxia
Causes of mechanical trauma
Abrasion, contusion, laceration, incision, avulsion
Abrasion
Superficial from friction : road rash
Contusion
Bruise
Laceration
Tearing from stretching
Incision
Cut by sharp instrument, wider than deep, like a surgical incision
Puncture wound
Piercing penetration of tissue caused by a sharp object, deeper than wider, like a stab wound
Avulsion
Tearing away of a body part, lawn mower accident
Localized hypothermia
Frostbite
Localized hyperthermia
Burns
Classifications of temperate injuries
Superficial- confined to epidermis
Partial thickness- injury to dermis
Full thickness- through the sub q tissue and causes damage to muscle- can lead to death
Factors influencing damage from ionizing radiation
Dosage, mode of delivery, and oxygenation of tissue
