which macromolecule would serve as an energy source for the cell and is used as a component in the cell wall of plants?

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

What is the difference between how ionic and covalent bonds form

Why do we perceive objects as retaining their brightness under different lighting levels?