Diseases, Conditions, Syndromes

Grand Canyon closed to public over coronavirus

The Grand Canyon was closed to visitors with immediate effect Wednesday, making the Arizona landmark visited by millions each year the latest tourist hotspot to shut over the coronavirus pandemic.

Medical research

Teeth serve as 'archive of life,' new research finds

Teeth constitute a permanent and faithful biological archive of the entirety of the individual's life, from tooth formation to death, a team of researchers has found. Its work provides new evidence of the impact that events, ...

Health

Home remedies: Acne affects people of all ages

Acne is a skin condition that occurs when your hair follicles become plugged with oil and dead skin cells. It often causes whiteheads, blackheads or pimples, and usually appears on the face, forehead, chest, upper back and ...

Immunology

Children allergic to cow's milk smaller and lighter

Children who are allergic to cow's milk are smaller and weigh less than peers who have allergies to peanuts or tree nuts, and these findings persist into early adolescence. The results from the longitudinal study—believed ...

Immunology

Don't let allergies spoil your holidays

(HealthDay)—Asthma or allergies can put a damper on holiday gatherings. But there are ways you can stay healthy, the American College of Allergy, Asthma and Immunology says.

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Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to 6 m; some authors set a minimum of 10 cm trunk diameter (30 cm girth). Woody plants that do not meet these definitions by having multiple stems and/or small size, are called shrubs. Compared with most other plants, trees are long-lived, some reaching several thousand years old and growing to up to 115 m (379 ft) high.

Trees are an important component of the natural landscape because of their prevention of erosion and the provision of a weather-sheltered ecosystem in and under their foliage. Trees also play an important role in producing oxygen and reducing carbon dioxide in the atmosphere, as well as moderating ground temperatures. They are also elements in landscaping and agriculture, both for their aesthetic appeal and their orchard crops (such as apples). Wood from trees is a building material, as well as a primary energy source in many developing countries. Trees also play a role in many of the world's mythologies (see trees in mythology).

This text uses material from Wikipedia, licensed under CC BY-SA