Question

Energy for ATP synthesis is obtained from
A. Oxygen ion gradient
B. Hydrogen ion gradient
C. Nitrogen ion gradient
D. All the above

Answer 1

Hint: Adenosine triphosphate (ATP) is an organic compound present in the human body and provides energy to perform different functions of the body. It helps in various functions like muscle contraction, chemical synthesis, nerve impulse propagation and condensate dissolution.

Complete answer:
Adenosine triphosphate helps in various energy requirements of our body when consumed in metabolic processes, it gets converted into simpler forms like adenosine monophosphate and adenosine diphosphate. ATP is also a precursor to DNA and RNA, and is used as a coenzyme.
ATP synthesis includes the transfer of electrons from the intermembrane space, as they move through the inner-membrane back to the matrix. This transfer of electrons from the matrix to the spaces of inter-membrane leads to a pH difference along the both sides of the membrane. It was recognized that there was a large energy difference, due to chemiosmotic potential occurring because of two components. One component is the difference in hydrogen ion concentration also known as hydrogen ion gradient and another component is electrical potential due to positive charged protons. This situation is positive out, negative in; basic in, acidic out. These two components provide energy for ATP synthesis by the multienzyme complex V of mitochondria which is responsible for ATP synthesis.

Hence, the correct option is B. Hydrogen ion gradient.

Note: The energy gradient across the membrane is the total of the energies due to these two components of the gradient that are hydrogen ion gradient and electrical potential.