Endocrine System: Hormones, Glands, and Health

Posted on Mar 8, 2025 in Biology

Endocrine System

The endocrine system is made up of endocrine glands that release hormones into the bloodstream.

Endocrine Glands

These include the thyroid gland, parathyroid gland, adrenal glands, pancreas, ovaries (in females), testicles (in males), and pituitary gland.

Hormones

Hormones are organic molecules produced by endocrine glands. They bind to receptors on target cells, regulating and coordinating organ functions.

Nervous System vs. Endocrine System

  • Nervous System: Fast action, short duration, uses nerve impulses.
  • Endocrine System: Slow action, longer duration, uses hormones.

Hypothalamus

The hypothalamus is an organ of the nervous system connected to the pituitary gland. It works in the following way:

  1. Neurons of the hypothalamus stimulate the pituitary gland to release hormones.
  2. These hormones travel through the blood and reach target cells of a gland.
  3. The gland produces a hormone, which travels through the blood to carry out specific functions.

Healthy Habits for the Endocrine System

  • Lead an orderly life.
  • Avoid drug consumption, as it can cause alterations in the nervous system.
  • Eat foods rich in vitamins B1, B3, and phosphorus to support nerve function.
  • Perform intellectual and mental exercises.

Health

Health is a state of complete physical, mental, and social well-being, not merely the absence of disease.

Symptoms and Signs

  • Symptoms: Signs that only the ill person notices.
  • Signs: Symptoms that help a doctor make a diagnosis.

Treatments

  • Curative: Aimed at recovering health.
  • Symptomatic: Aimed at alleviating symptoms.

Convalescence

After being cured, the body needs a period of time to fully recover, known as convalescence.

Diseases

  • Infectious vs. Non-infectious: Infections are caused by pathogenic microorganisms.
  • Acute vs. Chronic: Acute diseases last a short time, while chronic diseases last a long time.
  • Epidemic, Endemic, and Pandemic:
    • Epidemic: Affects many people in a short time.
    • Endemic: Exclusive to a specific region.
    • Pandemic: Affects many countries.

Pathogenic Agent

A pathogenic agent is a microorganism (bacteria, protozoa, fungi, or virus) that causes an infection.

Virulence

Virulence is the capacity of an agent to produce damage.

Infection Types

  • Local: Affects a specific area of the body.
  • General: Affects various organs.
  • Latent: The microorganism remains inactive until the body’s defenses are low, then it reproduces.

Infection Transmission

Infections can be transmitted through direct contact, contaminated objects, contaminated water or food, air, animals, and other means.

Defenses Against Infections: Immune System

External Defenses

External defenses prevent pathogens from entering the body. Types include:

  • Structural: Skin
  • Biochemical: Saliva
  • Mechanical: Mucus and cilia
  • Ecological: Symbiotic bacteria

Internal Defenses

Internal defenses include two types:

  • Non-specific: Phagocytosis and inflammatory response.
  • Specific: Antibody production.

Preventing Infectious Diseases

Vaccination: Involves introducing dead or inactive microbes to stimulate antibody production. Upon subsequent contact with the active pathogen, the immune system destroys it, preventing disease development.

Curing Infectious Diseases

  • Serum Therapy: Serum containing specific antibodies against a pathogen is injected into the infected person.
  • Antibiotics: Substances produced by fungi and bacteria that destroy or inhibit the reproduction of bacteria.

Transplants

A transplant is the transfer of an organ, tissue, or group of cells from a donor to a recipient whose organ or tissue is not functioning correctly. The main problem with transplants is rejection, a reaction of the immune system against the transplanted organ. Immunosuppressive medication is administered to prevent rejection, but it makes patients more vulnerable to infections.

Transfusions

A transfusion is a tissue transplant involving blood.

Cell Transplants

Cell transplants involve sets of cells that can regenerate one or more types of cells. There are two types:

  • Embryonic stem cells
  • Adult stem cells (which can only produce certain types of cells)

Endocrine Diseases

  • Diabetes: A disease in which blood glucose levels are very high. Insulin, a hormone, helps glucose enter cells for energy.
  • Gigantism: A hormonal disease caused by excessive secretion of growth hormone.