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Looking at the sun may not only cause headache and distort your vision temporarily, but it can also cause permanent eye damage. Any exposure to sunlight adds to the cumulative effects of ultraviolet (UV) radiation on your eyes. UV exposure has been linked to eye disorders such as macular degeneration, solar retinitis, and corneal dystrophies.
The term bacteria was devised in the 19th century by German biologist Ferdinand Cohn. He based it on the Greek word "bakterion" meaning a small rod or staff. Cohn is considered to be the father of modern bacteriology.
Amoebae are the simplest type of protozoans, and are characterized by a feeding and dividing trophozoite stage that moves by temporary extensions called pseudopodia or false feet.
The average older adult in the United States takes five prescription drugs per day. Half of these drugs contain a sedative. Alcohol should therefore be avoided by most senior citizens because of the dangerous interactions between alcohol and sedatives.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.