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Did you know?

Adolescents often feel clumsy during puberty because during this time of development, their hands and feet grow faster than their arms and legs do. The body is therefore out of proportion. One out of five adolescents actually experiences growing pains during this period.

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Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.

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Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.

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Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.

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According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.

Water potentials decrease (become more negative) as one moves from soil to plant to atmosphere Water potentials decrease (become more negative) as one moves from soil to plant to atmosphere
The eye. Lateral view of a sectioned eyeball in its socket. The eye. Lateral view of a sectioned eyeball in its socket.
Decrease in Fertility, 1800–1900 Decrease in Fertility, 1800–1900
Eric Clapton - Tears In Heaven Eric Clapton - Tears In Heaven
United States, southwestern and southern states are suffer from a significant decrease in rainfall United States, southwestern and southern states are suffer from a significant decrease in rainfall
Transverse section of posterior eyeball at optic disc Transverse section of posterior eyeball at optic disc
Video: Carbon fixing adaptations Animation

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