Unit 1 Flashcards
Define Pathophysiology
- Physiology gone wrong
- Study of the physiologic changes resulting from disease processes
Define Normal Condition
Body able to maintain a relatively stable internal environment (homeostasis)
-Ex: glucose range is 3.9-5.6mmol/L, Ca2+ range is 2.0-2.6 mmol/L and pH is 7.35-7.45
Define Disease State
Normal homeostatic mechanisms unable to compensate for the changes occurring in the body
Define Homeostasis
- Homeostasis is the maintenance of a stable internal environment around a physiological set point
- Ex: body temperature set is point is 37 degrees, blood pressure around 120/80, serum Ca2+ set at about 2.4 mmol/L and blood glucose concentration set at about 4.8 mmol/L
- In homeostasis, physiological systems that exercise mechanisms to maintain homeostatic set point
- When environmental changes occur, adaptations occur to adjust to the changes, for instance excessive demands placed on the system, failure in a regulatory control unit and control mechanisms, but the set point is altered
Origin of disease
- Genetic dysfunction
- Abnormality of physiological or biochemical function
- Abnormality of the gross structural arrangement of cells, tissues and organs
Cause of disease
- Endogenous causes (Inside) ex: genetic disorders
- Exogenous causes (outside) ex: poisoning
- Nutritional Causes: deficiency or excess in dietart intake
- Predisposing factors: special susceptibility to disease
- Risk factors of predisposing factors: characteristics that is statistically associated to disease, exposure may be the likelihood of developing disease ex: exposure to radiation may increase developing cancer
Define Cellular Adaptation
-Cellular homeostasis is constantly challenged by changes in the cellular environment, cell then may adapt to environmental changes through changing the set point for homeostasis
Define Ischemia
Decreased blood supply to an organ or tissue
Cell damage can be cause from (10 things)?
- Hypoxia (ischemia)
- Physical agents (heat, cold)
- Mechanical damage (pressure, tissue tearing)
- Chemical exposure (toxins, heavy metals)
- Infectious agents
- Abnormal Accumulation of metabolites
- Nutritional deficits
- Fluid and or electrolyte imbalance
- Free radical damage
- Electromagnetic radiation (UV)
Define reversible cell damage
- May occur is stressor is of short duration or causes minimal cell damage
- Cell may revoker after injurious agent is withdrawn
Define irreversible cell damage
- Cells die if noxious agent is lethal or allowed to persist
- 3 different mechanisms for cell death: immediate (occurs after massive trauma), Apoptosis (programmed cell death) and Necrosis (occurs as a result of severe damaging stimuli, group of cells die)
Define Necrosis (5 types)
- Coagulative necrosis: most common, cell proteins denature and typical after ischemic heart attack
- Liquifaction necrosis: semi-liquid appearance of tissue due to hydrolytic enzymes, common in brain ischemia and certain bacterial infection
- Fat necrosis: fatty tissue broken down into fatty acids by infections or enzymes
- Caseous necrosis: form of coagulation necrosis, thick and yellowish
- Gangrene: form of coagulative necorsis, ischemia lowers oxygen tension in tissue
What is the positive of necrosis?
Necrotic cells may release cellular proteins (ex: exocrine pancreas –> enxymes amylase). which help to aid in digestion
What is LDH?
It is a cellular protein found in all cells and when tissue is damaged it leaks out of the cells.
LDH = lactate dehyrogenase
