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Author Question: Animals with dorsal nerve cords are called A) phyla. B) chordates. C) vertebrates. D) ... (Read 87 times) |
Your skin wrinkles if you stay in the bathtub a long time because the outermost layer of skin (which consists of dead keratin) swells when it absorbs water. It is tightly attached to the skin below it, so it compensates for the increased area by wrinkling. This happens to the hands and feet because they have the thickest layer of dead keratin cells.
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.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The familiar sounds of your heart are made by the heart's valves as they open and close.
In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).