Nitrogenous base, sugar and phosphate
Although earthquakes often occur before a volcanic eruption, they are not the cause. The earthquakes are the result of magma (molten rock) moving underground leading up to an eruption. A few volcanic eruptions are thought to have been triggered or initiated by earthquakes, but this is not the typical case.
Answer:
B) FADH2 -- FMN of Complex I -- Fe-S of Complex II -- Q -- Fe-S of Complex III -- Cyt c -- Cyt a of Complex IV -- O2
Explanation:
FADH2 and NADH give their high energy electrons to the terminal electron acceptor molecular oxygen via an electron transport chain. As the electrons move through electron carriers of the electron transport chain, they lose their free energy. Part of the free energy of the electrons is used to pump the protons from the matrix into the intermembrane space. Therefore, part of the energy of electrons is temporarily stored in the form of a proton concentration gradient.
NADH gives its electrons to FMN of complex I while FADH2 gives its electrons to the Fe-S center of complex II. Both the complexes are oxidized by coenzyme (Q) which in turn reduces Fe-S centers of complex III. Cyt c of complex IV obtains electrons from complex III and passes them to CuA center, to heme "a" to heme "a3-CuB center" and finally to the molecular oxygen.
So, the compounds arranged with respect to the energy content of electrons in descending order are as follows: FADH2 -- FMN of Complex I -- Fe-S of Complex II -- Q -- Fe-S of Complex III -- Cyt c -- Cyt a of Complex IV -- O2.
