The correct option is THE ELECTRON IN THE OUTERMOST ELECTRON SHELL.
Different levels of energy exist in the atom of an element and these levels are filled with electrons. The electrons in the innermost shell has the lowest energy level while the electrons in the outermost shell has the highest energy level. For an electron to increase its energy level, it has to move to an higher shell; and to decrease its energy level it has to move to a lower shell.
The answer would be that the e<span>xcretion and the </span>liver<span>. Excretion in mammals. Excretion is the removal of potentially harmful or toxic substances from the </span>body<span>. These substances are usually waste materials </span>produced by<span> complex chemical reactions taking place in living </span>cells<span>. Enzymes catalyse the reactions.</span>
A virus that infects and replicates itself within bacteria.
