Explain why taking folic acid early in pregnancy is important to the prevention of neural tube defects.

Which set of characteristics best describes sedimentary rock? a) largest type of rock, made of organic matter, hardest type of rock b) often contains layers, forms near sources of water, contains fossils c) least abundant type of rock, made of other rocks, made mostly of minerals d) most abundant type in earth's crust, made of magma/lava, contains no fossils

How does the carbon cycle involve an exchange of carbon

What processes take place before the mature mrna exits the nucleus?