Fill in the blanks about each of the following sequential steps of the electron transfer chain (ETC) of the inner mitochondrial membrane. a. The initial electron donor of the ETC is , which hands its two electrons off to FMN, within Complex I.
b. Electrons from both Complex I and Complex II are ultimately donated to the same molecule, .
c. Within Complex III, electrons from ubiquinol are ultimately donated to , which then passes those electrons on to Complex IV.
d. is the final electron acceptor of the ETC.
e. The downhill movement of electrons through the ETC creates a proton gradient across the inner mitochondrial membrane. The subunit of the ATP synthase creates a channel that allows for the downhill movement of protons from the intermembrane space to the matrix.
f. The concomitant release of free energy drives the synthesis of ATP by the subunit of that same protein.

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.  

examples of nucleic acids are deoxyribonucleic acid (dna) and ribonucleic acid (rna).