Transcript Introduction to Systems and Diseases

Introduction to
Systems and Diseases
Levels of body organization
Tissues – A group of cells working
together for a common function
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Epithelial tissue
Connective tissue
Muscular tissue
Nervous tissue
Anatomy
• The study of structure
Physiology
• The study of function
Pathology
• The study of disease
Homeostasis
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Balance
Internal dynamic equilibrium
Maintains health
Lose homeostasis and you’re sick
Disease
• Characterized by signs and symptoms
• Signs are objective – e.g. body
temperature
• Symptoms are subjective – e.g. tired
Inflammation
• “-itis” is suffix meaning inflammation; e.g.
dermatitis
• Alerts us to a problem
• Isolates and/or removes damaged cells
• Prepares for healing
Inflammation
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Signs and symptoms:
Red
Heat
Swelling
Pain
• Acute – sudden illness, short-lived; e.g. 24
– hour flu
• Chronic – gradual long-term illness; e.g.
osteoarthritis
Infection
• The presence and multiplication of
microorganisms
• Note: MOST microorganisms do NOT
cause disease, but we will only talk about
those that do
Bacteria
Bacteria
Virus
Parasite
Modes of obtaining infection
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Airborne
Direct contact
Ingestion
Normal inhabitant of body
Mom to fetus
Sexually transmitted
Modes of obtaining infection
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Animals
Insects
Blood transfusion
Other