It is mostly likely the cell membrane.
The cell membrane is a structure of a cell composed of double layer of lipids and proteins. It surrounds a cell and separates the cytoplasm from its surrounding environment. The cell membrane is selectively permeable (semi-permeable), which means that it only lets certain molecules enter and exit. It can also control the amount of some substances that go into or out of the cell.
<span>Bonds between atoms are broken and new bonds are formed.</span>
Chromosomes females have xx and males are xy
1. Oxidized
2. Reduced
3. Glucose
4. Pyruvate
5. NAD+
6. NADH
An acronym for understanding gain and loss of electrons is OIL RIG (Oxidation is Loss of electrons, Reduction is Gain of electrons).