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Health | Human Body | Body Systems

Your body is pretty amazing. At any given point you have many biological processes going on -- circulatory, digestive, brain & central nervous systems and more. Learn about these body systems as well as the eye, ears, nose and throat.

Brain & Central Nervous System

Brain & Central Nervous System

The brain performs an incredible number of tasks and nervous system is a network of specialized tissues that regulates thoughts, sensations, basic body functions and more. Explore the many functions of the brain & the central nervous system. See more »

Circulatory System

Circulatory System

The heart is a hollow, muscular organ that maintains blood circulation throughout the body. Learn how the circulatory system - your heart, blood vessels and blood - bring nutrients to the body. See more »

Digestive System

Digestive System

The digestive system is in charge of absorbing and transporting nutrients your body needs in order to thrive -- and it gets rid of all the waste the body doesn't need. Discover how saliva breaks down the food you eat and more. See more »

Endocrine System

Endocrine System

The endocrine system comprises a number of glands that produce hormones with a varied array of vital functions. Learn more about how the adrenal glands, pituitary glands and the pancreas works. See more »

Eye, Ear, Nose & Throat

Eye, Ear, Nose & Throat

The eyes, ears, nose and throat are interconnected organs that are vital parts of several body systems. Discover how these organs work as well as conditions that can affect them. See more »

Immune System

Immune System

Inside your body, there is a mechanism designed to defend you from millions of bacteria, microbes, viruses, toxins and parasites. Find out the different components and how the human immune system works. See more »

Kidney & Urinary Tract

Kidney & Urinary Tract

The role of the urinary system is to cleanse the blood. Arterial blood is filtered through the kidneys and returned to the circulation. Learn more about how the urinary system monitors the concentration of salts and other necessary nutrients. See more »

Lymphatic System

Lymphatic System

The lymph system is the body's drainage system. It is composed of a network of vessels and small structures called lymph nodes. Explore the difference between antibodies and the immune system. See more »

Musculoskeletal System

Musculoskeletal System

Bones and muscles -- the musculoskeletal system -- are what make the body move. Learn how every movement of the body is the result of the coordination of bones, muscles, tendons, and ligaments. See more »

Respiratory System

Respiratory System

The respiratory system includes the nose, throat, larynx, trachea, bronchi, and lungs. Discover how the respiratory system supplies blood with necessary oxygen and relieves it of the waste product carbon dioxide. See more »

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