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Author Question: Within the control region of the trp operon is a section of DNA that is sensitive to levels of ... (Read 52 times) |
The average adult has about 21 square feet of skin.
Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.
In most cases, kidneys can recover from almost complete loss of function, such as in acute kidney (renal) failure.
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.
Vaccines prevent between 2.5 and 4 million deaths every year.