Main Idea Reassessment

Wilbur and Orville Wright were brothers who were inventors, even from a young age when they built kites and bicycles. Many people credit the Wright Brothers with designing and building the first successful airplane. In 1903, their first flight only lasted 12 seconds, but it continues to inspire people all over the world to learn about science and math, to work hard to realize their dreams, and to use imagination to achieve success.

Did you know that giraffes are the tallest animals in the world? They are unique in other ways, too. For one thing they sleep only about 20 minutes each day, and usually not more than five minutes at a time. (They have to remain alert for predators.) Also, every giraffe's coat is unique and varies in color from white to nearly black, depending on what they eat and where they are.

Working dogs are amazing animals specially trained to protect people and to make life easier for them. Some working dogs act as eyes for blind people, ears for the hearing impaired, and helpers for the physically challenged. Others help ranchers protect and move sheep and cattle from place to place. Police dogs help officers catch criminals, find illegal drugs and weapons. Search dogs are trained to find disaster victims and missing people.

Inventors in Belgium have created a device that might enable thousands of blind people to see. The invention includes a small video camera mounted on eyeglasses.

Blindness can occur for many different reasons. One reason is damage to the retina, the membrane that lines the inner eyeball. The retina picks up visual messages in the form of light. Then it sends those messages to the brain through the optic nerve. If a person's retina is not working, messages are not sent to the brain.

The Belgian scientists created a tiny electronic device that takes over for a damaged retina. They implant the device inside the blind person's head, just behind the eye. The patient wears a pair of glasses with a little video camera mounted on them. The camera takes pictures and sends the images to the implant in the head. Then the implant electronically stimulates the optic nerve, sending the visual images to the brain. The scientists have tested the device in two patients. The results have been promising.