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Author Question: ____ new menu now includes many low-calorie and low-fat options. A) McDonald's B) McDonald's' C) ... (Read 116 times) |
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.