Answer:
Cell membrane of prokaryotes and Inner mitochondria of eukaryotes
Explanation:
Electron transport chain is a part of oxidative phosphorylation which is the third step of aerobic cellular respiration in living organisms. The ETC is a complex of proteins and mobile electron carriers. It occurs when electron is being transferred from one electron carrier to another, starting from NADH and FADH2. A proton pump which is used to synthesize ATP is generated at the end.
This ETC process occurs in the cell membrane of prokaryotic cells due to the fact that they lack a membrane-bound Mitochondrion. ETC occurs in the inner membrane of the mitochondria called CRISTAE in eukaryotic cells.
Transcription<span> is the process of converting the message in </span>DNA<span> into </span>mRNA<span>, this is where </span>mutations<span> can first occur. </span>Mutations<span> at the level of </span>DNA<span>can affect the production of </span>proteins<span> in the long run.</span>
Positron Emission Tomography scan of the brain of cocaine addicts showed that the drug affects how the brain use glucose. Cocaine users' brain cannot use glucose efficiently and there are also reduced metabolic activity in other areas of the brain.