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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.
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.
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.
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.
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.
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.
The skin is the largest organ of the body, covering 18 square feet and weighing about seven pounds in an average adult. Explore the three layers of skin -- the epidermis, the dermis, and the subcutaneous layer.
The female reproductive system consists of those structures within the female body designed to create and nourish new life. The system includes the ovaries, fallopian tubes, uterus, cervix, and vagina.
The male reproductive system consists of those structures in the male body designed to create life. The system includes the testes, a network of ducts, seminal vesicles, the prostate gland, and the penis.
Roses are red, violets are blue -- well, bluish. The sky is blue, too. Grass is green. These are things that most of us know for a fact and don't question. But what if you were colorblind? What would you see? Is life one long black-and-white movie?
Smell is a basic sense, but scientists are still exploring how it works. Why are researchers, developers and even government agencies so curious about smell? What makes a seemingly simple sense so tantalizing?
Watch this video from the University of Chicago showing results of an empathy test. Researchers have shown that some people can turn on and off their empathy switch - such as doctors that have to inflict pain to ultimately help patients.