Atoms may have different numbers of neutrons. Atoms are the smallest fraction of an element that can exist, and still show the properties of the element. They consists of electrons (negatively charged), protons (positively charged), and neutrons (no charge). The number of electrons is equivalent to the number of protons normally however an atom may loose or pick up electrons and have a positive charge or negative charge. The number of neutrons in the nucleus may vary within a given element to give varieties of atoms we call isotopes.
Example - the relatively rigid covering of a plant cell, containing cellulose, hemicellulose, lignin, etc.<span>
non example - </span><span>Mycoplasma because it has no cell wall</span>
The answer is B. because the electron transport chains produces the most atp.
provide the barrier that marks the boundaries of a cell.
