Paleontologists study the remains of organisms that lived in the past. many of these remains are preserved in rocks.

which two parts of the earth system is a paleontologist involved in?

a. lithosphere and atmosphere

b. hydrosphere and atmosphere

c. biosphere and lithosphere

d. biosphere and magnetosphere

cell regulation is conducted by special proteins.

in a chemical reaction, the atoms and molecules produced by the reaction are called products. no new atoms are created, and no atoms are destroyed. in a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.