Answer:
Option A, a compound that contains carbon atoms bound to other elements
Explanation:
An organic compound is one which has at least one carbon atom that is bonded to several other atoms (may be metallic or non metallic) by a single or double bond is termed as organic compound . The most common atoms with which carbon forms bond are hydrogen, nitrogen,and oxygen.
Some common examples are -
Methane - 
Methanol - 
Hence, option A is correct
Answer:
Facilitated diffusion
Explanation:
Oxidative phosphorylation, involving the Electron transport chain and Chemiosmosis is the third stage of cellular respiration. The main purpose of the ETC is to build an electrochemical (electrical and concentration) gradient across the inner mitochondrial membrane. It does this by using energy to pump protons (H+ ions) from the matrix to the inter-membrane space of the mitochondria.
Facilitated diffusion, also known as passive transport through channels, is a form of facilitated transport involving a passive movement of molecules along their concentration gradient, through channels called membrane proteins.
During Chemiosmosis of Oxidative phosphorylation, protons (H+) flow back down their concentration gradient (from inter-membrane space to matrix) due to the chemiosmotic gradient that has been formed in ETC. However, hydrogen ions (H+) cannot pass through the inner mitochondrial membrane except through an enzyme (protein) found in the inner mitochondrial membrane called ATP synthase. This protein acts as a machine powered by the force of the H+ diffusing through it, down an electrochemical gradient. This movement of H+ via ATP synthase further catalyzes the conversion of ADP to ATP.
It is an example of facilitated diffusion because H+ ions are diffusing across the inner mitochondrial membrane (from inter-membrane space to matrix) via a protein channel or membrane protein called ATP synthase.
Electron microscopy would be most useful in observing the structure of a virus
Those cells are called neurons
