Answered

When NADH is the electron donor to the respiratory chain, 2.5 ATP are formed, but when FADH2 is the electron donor, only 1.5 ATP are formed. This difference occurs because _____.

Answer :

Answer:NADH donates it electron to complex I a higher energy level than other complexes while FADH donates it electron to complex II a lower energy complex.

Explanation:

Both NADH and FADH are shuttle of high energy electrons originally extracted from food into the inner mitochondrial membrane.

NADH donate it electron to a flavoprotein consisting of FMN prosthetic group and an iron-sulphur protein in ETC complex-I. Two electrons and one hydrogen ion are are transferred from NADH to the flavin prosthetic group of the enzyme.

While the electrons from FADH2 enters the ETC (electron transport chain) at the level of co-enzyme Q (complex II). This step does not librate enough energy to act as a proton pump.

So NADH produces 2.5 ATP during the ETC and oxidative phosphorylation because it donates its electron to Complex I, which pump more electrons across the membrane than other complexes.

This difference occurs because during phosphorylation oxidation the complex I can accept electrons from NADH but not FADH2.

What is cellular respiration?

Cellular respiration refers to a series of chemical reactions to produce ATP by using foods and oxygen.

  • Cellular respiration has three main stages which include glycolysis, the Krebs cycle and oxidative phosphorylation.

  • During phosphorylation oxidation, a gradient of protons is coupled to the movement of electrons from NADH and FADH2 in a series of protein complexes to generate ATP.

In conclusion, this difference occurs because during phosphorylation oxidation the complex I can accept electrons from NADH but not FADH2.

Learn more in:

https://brainly.com/question/8562250

Other Questions