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Author Question: The _____ is the inner layer of the embryo from which the lungs and digestive system develop. A) ... (Read 54 times) |
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Blood is approximately twice as thick as water because of the cells and other components found in it.
Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
The first monoclonal antibodies were made exclusively from mouse cells. Some are now fully human, which means they are likely to be safer and may be more effective than older monoclonal antibodies.