Water is a polar covalent molecule
Energy flows up a food chain, from the primary producers to the primary consumers, to the secondary consumers, up to the tertiary and then quaternary consumers. Energy flows when one organism eats another lower in the food chain, the energy is transferred by heat and movement, some though is lost. They eat each other but it only gets half the energy stored. A food web is similar - it is just a series of food chains.
A. Nucleotides; they are molecules that form basic structural units
True. Artificial selection can cause defects ect.
