« previous next »
« previous next »
 

Did you know?

Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.

Did you know?

Your heart beats over 36 million times a year.

Did you know?

In ancient Rome, many of the richer people in the population had lead-induced gout. The reason for this is unclear. Lead poisoning has also been linked to madness.

Did you know?

The toxic levels for lithium carbonate are close to the therapeutic levels. Signs of toxicity include fine hand tremor, polyuria, mild thirst, nausea, general discomfort, diarrhea, vomiting, drowsiness, muscular weakness, lack of coordination, ataxia, giddiness, tinnitus, and blurred vision.

Did you know?

Historic treatments for rheumatoid arthritis have included gold salts, acupuncture, a diet consisting of apples or rhubarb, nutmeg, nettles, bee venom, bracelets made of copper, prayer, rest, tooth extractions, fasting, honey, vitamins, insulin, snow collected on Christmas, magnets, and electric convulsion therapy.

A comparison between chromosomes found in a normal human cell and a cancer cell from the same person A comparison between chromosomes found in a normal human cell and a cancer cell from the same person
The visual field as seen by a person with (a) glaucoma, (b) macular degeneration, and (c) cataracts. The visual field as seen by a person with (a) glaucoma, (b) macular degeneration, and (c) cataracts.
Photograph of a person with a cataract in the right eye. Photograph of a person with a cataract in the right eye.
Edward Bellamy, author of the utopian novel Looking Backward (1888) Bellamy’s socialism worried many Edward Bellamy, author of the utopian novel Looking Backward (1888) Bellamy’s socialism worried many
How Much Food Does the World Produce Per Person? How Much Food Does the World Produce Per Person?
(left) Urine sample from an unaffected person does not change color upon exposure to air. (right) Ur (left) Urine sample from an unaffected person does not change color upon exposure to air. (right) Ur
Video: Regulation of GFR: autoregulation via myogenic mechanism Myogenic mechanism

For a complete list of videos, visit our video library