Sneezes are a reflex usually caused by foreign particles irritating the nostrils. This videoidentifies factors that lead to sneezing, the purpose of a sneeze, and what happens in the body during a sneeze.

"Discover how different animals use their eyes to hunt, scare other animals, or stay safe"--Provided by publisher.

Simple text introduces the functions of the human eye, as well as tools that can help people who have vision problems.

Age-related macular degeneration-AMD-is the most commonly diagnosed eye disorder in people over fifty. Well over two million Americans have been told they have AMD, and that number is expected to grow substantially. While this is a frightening statistic, over the last several years, medical researchers have shown that a number of effective treatments can slow, stop, and even reverse the progress of AMD. Now, best-selling authors Dr. Jeffrey Anshel...

Dr. Alice Roberts undergoes a thorough eye examination in this episode of her tour of the body's major organs. She puts her own body to the test, beginning with a 250-foot climb up a sheer cliff face - blindfolded. She also meets Sarah, who has a family history of eye problems, and sets out to discover if her computer- and TV-dependent lifestyle is affecting her sight. In addition, Dr. Roberts investigates whether carrots really are good for the eyes...

The deadliest natural weapon employed in the animal kingdom has independently evolved in creatures as diverse as jellyfish, insects, snakes, and even mammals. In this program, scientists show how evolution has adapted venom to fit the needs of the animals who wield it.

You blink an average of 15 times a minute, moving lubricating fluid from your lacrimal glands across your eyes. Blinking also helps prevent harmful substances like smoke from getting in your eyes and protects your eyes from foreign objects. When your eye is irritated, your lacrimal gland produces extra tears to wash out impurities. As fluid drains through your tear ducts and into your nasal cavity, it may cause you to sniffle.

I'm Dr. Alan Greene and let's talk about what do you do when something gets in the eye.

A young Asian boy notices that his eyes look different from his peers' after seeing his friend's drawing of them. After talking to his father, the boy realizes that his eyes rise to the skies and speak to the stars, shine like sunlit rays, and glimpse trails of light from those who came before-in fact, his eyes are like his father's, his agong's, and his little brother's, and they are visionary. Inspired by the men in his family, he recognizes his...

Cataracts may develop with advancing age or in response to diseases such as diabetes. A cataract appears as a cloudy area in the lens.