It is ratio of volume of CO₂ evolved and volume of O₂ consumed.
R.Q. = Volume of CO₂ evolved / Volume of O2 consumed
For proteins: R.Q. remains 0.9 and the R.Q. for fat is 0.7
2C₅₁H₉₈O₆ + 145O₂→ 102CO₂ + 98H₂O + Energy
R.Q. = 102/ 145 = 0.7

ATP synthatase consists of F0F1 particles. Fo acts as channel through which H+ passes.
F1 contains the site for synthesis of ATP.

Glycolysis produces only two net molecules of ATP per 1 molecule of glucose. However, in cells lacking mitochondria and/or adequate oxygen supply, glycolysis is the sole process by which such cells can produce ATP from glucose.

During oxidative phosphorylation ATP is synthesised by the ATP synthase enzyme when the chemiosmotic gradient is used to drive the phosphorylation of ADP. The electrons are finally transferred to exogenous oxygen and, with the addition of two protons, water is formed.

Pyruvic acid, the product of glycolysis can undergo any of the following three processes for further oxidation and energy release:
(i) Lactic Acid Fermentation
(il) Ethanol Fermentation
(iii) Krebs' Cycle

Glycolysis, which involves breaking down of sugar to form pyruvic acid, is the first step in cellular respiration.

Cellular respiration involves oxidation of glucose to produce energy, trapping of that energy and utilization of that energy. All of this happens inside a cell.
Following is the equation for respiration.
C₆H₁₂O₆ + 60₂ \(\rightarrow\)6CO₂ + 6H₂O + 674 kcal

the stepwise release of energy have advantage to the cell. Because if all the energy from the glucose would be released at once then most of it would be lost in the form of light and heat. This energy is trapped in ATP is utilised in various energy-requiring processes of the organisms and for the synthesis of the other biomolecules in the cell.

The RQ of value 4 is expected from oxalic acid because it is an organic acid, whenever organic acids are oxidised, then RQ value is always greater than one.

The RQ will be infinity (\(\infty \)) during anaerobic respiration. In anaerobic respiration, CO₂ is evolved, but oxygen is not used. Therefore, RQ in such a case, will be infinite.
e.g.,  \({ C }_{ 6 }{ H }_{ 12 }{ O }_{ 6 }\rightarrow 2{ C }_{ 2 }{ H }_{ 5 }OH+2{ CO }_{ 2 }+Energy\)
\(RQ\quad =\frac { 2{ CO }_{ 2 }(2molecules) }{ { O }_{ 2 }(zero\quad molecules) } -Infinity.\)

Cytochrome-c is attached to the outer surface of the inner membrane of mitochondria.
It acts as a mobile carrier for transfer of electrons between complex III and complex IV.

(i) It acts as the the terminal acceptor of hydrogen.
(ii) It drives the whole process by removing hydrogen from the system.

The main steps in aerobic respiration are as follows
(i) Glycolytic breakdown of glucose into pyruvic acid.
(ii) Oxidative decarboxylation of pyruvic acid to acetyl Co-A(acetyl coenzyme-A)
(iii) Krebs' cycle.
(iv) Terminal oxidation and phosphorylation in respiratory chain.
It occurs inside the mitochondrial matrix.

Anaerobic respiration also called fermentation. It involves the production of energy from food nutrients in the absence of oxygen. Organic compounds produced in the process of oxygen.Organic compounds produced in the process.
(i) Ethyl alcohol in yeast cell
(ii) Lactic acid in muscles.

Substrate level phosphorylation is a type of metabolism that results in the formation and creation of Adenosine Triphosphate(ATP) or Guanosine Triphosphate (GTP) by the direct transfer and donation of a phosphoryl (PO₃) group to Adenosine Diphosphate (ADP) or Guanosine Diphosphate (GDP) to form a phosphorylated reactive intermediate.