human disease

Table of Contents

Introduction
Health versus disease
Maintenance of health
- Homeostasis
  - Fluid and electrolyte balance
  - Acid-base equilibrium
  - Thermoregulation
  - Metabolic control
- Adaptation
- Defense against biotic invasion
  - Maintenance of the integrity of skin and mucosal linings
  - Phagocytic cells of the body
  - The inflammatory response
  - The immune response
- Repair and regeneration
- Hemostasis
- Interrelationship of defensive mechanisms
Disease: signs and symptoms
The causes of disease
- Diseases of genetic origin
  - Factors relating to genetic injury
  - Heredity and environment
- Chemical and physical injury
  - Chemical injury: poisoning
    - Organic chemicals
    - Inorganic chemicals
    - Drugs
  - Physical injury
    - Injuries from cold or heat
    - Electrical injuries
    - Pressure-change injuries
    - Radiation injury
- Diseases of immune origin
  - Immune deficiencies
  - Immune responses in the absence of infection
    - Allergies
    - Autoimmune disorders
    - Graft rejection
- Diseases of biotic origin
  - Factors in infection
    - Infectious agents
    - Invasiveness and virulence
    - Predisposition of the host
  - Viral diseases
  - Rickettsial diseases
  - Bacterial diseases
  - Fungi and other parasites
- Abnormal growth of cells
  - Normal and abnormal cell growth
    - Cell growth inhibition
    - Neoplasms: malignant and benign tumours
  - Characteristics of cancer
    - Epidemiology
    - The role of genetics
    - Heredity and environment
  - Carcinogenic agents
    - Chemicals
    - Radiant energy
    - Viruses
- Diseases of metabolic-endocrine origin
- Diseases of nutrition
  - Diseases of nutritional excess
  - Diseases of nutritional deficiency
- Diseases of neuropsychiatric origin
  - Psychiatric diseases
  - Neurological diseases
    - Alzheimer’s disease
    - Huntington’s chorea
    - Parkinson’s disease
- Diseases of senescence
Classifications of diseases

References & Edit History Related Topics

Images & Videos

The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

How to boost energy without caffeine

What is the purpose of electrolytes?

lung congestion

Why do people have allergies in the spring?

Read Next

Hand washing. Healthcare worker washing hands in hospital sink under running water. contagious diseases wash hands, handwashing hygiene, virus, human health

17 Questions About Health and Wellness Answered

Illustration showing electrical activity of the human brain

5 Common Misconceptions About Schizophrenia

Discover

A human Inuit skull in a stone chambered cairn in Ilulissat in Greenland. These ancient graves are pre christian and are at least 2000

14 Tough Questions Answered

Iraqi Army Soldiers from the 9th Mechanized Division learning to operate and maintain M1A1 Abrams Main Battle Tanks at Besmaya Combat Training Center, Baghdad, Iraq, 2011. Military training. Iraq war. U.S. Army

8 Deadliest Wars of the 21st Century

Diverse elementary school children wearing school uniforms running outside of school. Boys girls

Pro and Con: School Uniforms

Title: Senate Square, St. Petersburg, December 14, 1825: repression of the troop mutiny - watercolor by Carl Ivanovitch Kollman, 1825 depicts Decembrist uprising clashing with cavalry, with spectators watching. (new style December 26, 1825) Europe. Saint

8 of the Largest Empires in History

An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.

11 Egyptian Gods and Goddesses

Thumbnail for flags that look alike quiz Russia, Slovenia, Iceland, Norway

Flags That Look Alike

Leonardo da Vinci (1452-1519), Italian Renaissance painter from Florence. Engraving by Cosomo Colombini (d. 1812) after a Leonardo self portrait. Ca. 1500.

10 Famous Artworks by Leonardo da Vinci

human disease: Related Content

Written and fact-checked by The Information Architects of Encyclopaedia Britannica

Photos and Videos

The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

lung congestion

How to boost energy without caffeine

What is the purpose of electrolytes?

Why do people have allergies in the spring?

See All Videos and Images →

Topics

cardiovascular disease mental disorder nervous system disease digestive system disease nutritional disease childhood disease and disorder respiratory disease human genetic disease eye disease blood disease disability human behaviour therapeutics plant disease human nutrition medicine human evolution sleep animal disease diagnosis

Dig Deeper: More Articles That Discuss This Topic

Quiz

44 Questions from Britannica’s Most Popular Health and Medicine Quizzes

3d illustration human heart. Adult Anatomy Aorta Black Blood Vessel Cardiovascular System Coronary Artery Coronary Sinus Front View Glowing Human Artery Human Heart Human Internal Organ Medical X-ray Myocardium

Medical Terms and Pioneers Quiz

List

Hand washing. Healthcare worker washing hands in hospital sink under running water. contagious diseases wash hands, handwashing hygiene, virus, human health

17 Questions About Health and Wellness Answered