Human Body Systems: Diseases, Illnesses & Health

Health and Illness

What is Health?

Health, as the absence of illness, is the state of well-being of the body. When healthy, the body carries out all its functions correctly. Healthy habits help us stay healthy and prevent illnesses. A healthy diet is one of the most important habits.

What is Illness?

An illness is an abnormal process that alters, modifies, or prevents the activity of part of our body or the complete organism.

• Infectious diseases are caused by microorganisms, viruses, or bacteria (e.g., the flu).
• Congenital illnesses exist at birth (e.g., blindness).
• Hereditary illnesses are transmitted from parents to offspring (e.g., color blindness).
• Deficit disorders result from a lack of vitamins, minerals, or other essential substances (e.g., scurvy).
• Chronic illnesses are prolonged and incurable, though often treatable (e.g., chronic bronchitis).

Note: Some congenital diseases are also hereditary.

Epidemics and Pandemics

An epidemic affects a community (city, country, or region). (e.g., the flu). A pandemic affects a large territory (one or more continents).

Common Illnesses

Caused by Viruses

The common cold is highly contagious, causing slight discomfort, increased nasal secretions, congestion, and sneezing. It spreads through contact and sometimes through the air.

Caused by Bacteria

Salmonella, caused by contaminated food, leads to high fever and serious digestive disorders. It is treatable with antibiotics.

Caused by Fungi

Athlete’s foot, affecting the feet, often occurs in swimming pools and is linked to poor hygiene.

Caused by Protozoa

Malaria, transmitted by mosquito bites in tropical areas, introduces protozoa into the body.

Vaccination

Vaccination involves introducing a vaccine containing disease-causing microorganisms or their toxins into the body.

System-Specific Illnesses

Digestive System

Cavities are the progressive destruction of teeth due to bacteria. Proper dental hygiene and regular dental visits help prevent them.

Respiratory System

Bronchitis, an inflammation of the bronchi due to bacterial infection, is treated with antibiotics. Monitoring is crucial to prevent chronic conditions.

Circulatory System

Angina, caused by narrowed coronary arteries, results in chest pain lasting several minutes, typically resolving with rest. It usually doesn’t have serious consequences.

Excretory System

Cystitis, bladder inflammation, often caused by cold, is treatable with antibiotics.

Nervous System

Alzheimer’s syndrome causes progressive memory loss and impaired reasoning, stemming from a chemical process destroying or disrupting brain neuron communication.

Sensory Organs

Cataracts, common in older people, involve the lens of the eye becoming opaque. While not causing blindness, they impair vision and are treatable with surgery.

Endocrine System

Diabetes, a common illness affecting pancreas function, has various types. The common type involves insufficient insulin secretion. Treatment often involves insulin supplementation.

Alterations in growth cause dwarfism (deficient growth) or gigantism (exaggerated growth). These conditions are linked to the hypophysis hormone and are often treatable with medical intervention.

Sexually Transmitted Diseases

AIDS severely weakens the immune system, causing various disorders, fever, cancer, hemorrhaging, and often death.

Candidiasis causes vaginal irritation and discharge in women and less frequently, inflammation of the glans in men.

Methods of Birth Control

Condoms are highly effective and have few disadvantages. Spermicides, while easy to use, are less effective and may cause allergic reactions.

Assisted Reproduction

Artificial insemination involves introducing sperm into the vagina artificially. In vitro fertilization involves fertilizing ova outside the body and then implanting the embryo into the uterus.