1 - Introduction, Cell Adaptation (Exam 1) Flashcards
What are the 2 divisions of pathology?
- General Pathology - changes that occur at a molecular, cellular, and tissue level due to disease
- Systemic Pathology - changes that specialized organs within organ systems have due to disease.
What are 8 common causes of cell injury?
- Infectious agents
- Genetic defects
- Oxygen deprivation
- Chemical agent exposure (exogenous/endogenous)
- Physical agent exposure
- Nutritional imbalance
- Immunologic Reactions
- Aging
What are 4 forms of cell adaptation?
- Atrophy
- Hypertrophy
- Hyperplasia
- Metaplasia
What is atrophy?
Shrinkage in the size of a cell due to loss of cell substances. Protein degradation plays an important role.
What are 6 causes of atrophy?
- Reduction in blood supply
- Loss of nerve innervation
- Decrease in workload
- Reduction in nutrition
- Reduction in endocrine stimulation
- Aging
What is hypertrophy?
Increase in the size of a cell, can be either physiologic or pathologic.
What are 2 examples of causes of physiologic hypertrophy?
- Skeletal muscle cells enlarge as a result of increase in functional demand such as exercise.
- Uterine enlargement during pregnancy due to estrogen stimulation.
What are 2 main causes of pathologic hypertrophy?
- Genetic defects (example - hypertrophic cardiomyopathy)
2. Secondary abnormal hormonal stimulation (example - Cushings Disease secondary to overproduction of ACTH)
What is an ocular example of pathologic hypertrophy?
Congenital Hypertrophy of the Retinal Pigmented Epithelium (CHRPE)
What is hyperplasia?
An increase of the number of cells in an organ or tissue. Can be physiologic or pathologic.
What are the 2 divisions of physiologic hyperplasia?
- Hormonal hyperplasia
2. Compensatory Hyperplasia
What is hormonal hyperplasia?
Cell count increase with hormone stimulation, common in mammary tissue.
What is compensatory hyperplasia?
New cells replacing lost cells, common with hepatocytes of the liver.
What is a typical cause of hormonal hyperplasia?
Excess hormonal/growth factor stimulation (example - papillomavirus causing tropic stimulation of skin cells)
What is metaplasia?
A reversible change in which an adult cell is replaced by another adult cell type, more common in epithelial cells or connective tissue.
Why does metaplasia occur?
To make the tissue more able to withstand stresses, may result in a loss of some function.
What are 2 examples of metaplasia?
- Pseudostratified ciliated columnar epithelium to stratified squamous epithelium in the respiratory tract.
- Transformation of non-bone connective tissue into bone.
What are the 2 types of Cell Injury?
- Reversible
2. Non-Reversible
What are reversible cell injuries?
Non lethal, where cells can return to normal function after the injury.
What are non-reversible cell injuries?
Lethal, cells die and therefore can not return to normal function.
What are the 2 types of non-reversible cell injuries?
- Necrosis
2. Apoptosis
What is necrosis?
Cell death occurring most often after loss of blood supply, may cause severe tissue dysfunction.
What is apoptosis?
Death of cells by way of programmed death process, normal, and results in minimal tissue dysfunction.
Hypoxia and Anoxia are 2 types of ‘inadequate oxygenation’, how are they different?
Hypoxia is a reduction of oxygen
Anoxia is the complete absence of oxygen
What are 3 respiratory causes of inadequate oxygenation?
- Inadequate ventilation
- Reduction in functional respiratory surface (example - pneumonia)
- Elevation change
What are 3 vascular causes of inadequate oxygenation?
- Anemia - reduction in oxygen carrying capacity of the blood
- Poisoning - CO binding to hemoglobin
- Ischemia - reduction in blood supply to tissue (most common cause)
What are examples of infectious agents?
Microbes and parasites, such as:
Viruses, prions, bacteria, fungi, protozoa, helminths
What are examples of chemical agents?
Toxins, such as:
Pollution, insecticides, and drugs.
Also, high enough concentration of things like oxygen, glucose, and salts can change cell/tissue osmolarity.
What are the two types of reactions associated with Chemical Agents?
- Physical reaction
2. Chemical reaction
What are examples of genetic defects that cause cell injury?
- Congenital malformations
- Teratogenic effects (from drugs that cause abnormal fetal development)
- Neoplasia (tumors)
Immunologic reactions are meant to protect the body. What are 2 types of immunologic reactions that may cause cell injury?
- Hypersensitivity/anaphylaxis
2. Autoimmune disease
What are the 5 types of physical agents that result in cell injury?
- Mechanical (trauma)
- Radiation
- Electrical shock
- Temperature extremes
- Changes in atmospheric pressure
What are the two types of nutritional imbalances?
- Deficiency
2. Excess
What 3 types of nutritional deficiency will cause cell injury?
- Protein - caloric
- Vitamins
- Minerals
What 4 types of nutritional excess will cause cell injury?
- Vitamins
- Iron
- Calcium
- Fat - very common in the USA
How is aging related to cell injury?
Cells lose the ability to divide and grow
Structure and function of cells change over time, leads to a reduce capacity to respond to injury
