Energy released by oxidation in respiration:
1. can use only carbohydrates as respiratory substrate
2. is all released free into the cell
3. is all released in a single step
4. cannot be used directly

Plants can get along without respiratory organs. What may be the reason/s for this?
I. Each plant part takes care of its own gas exchange needs
II. Plants do not present great demands for gas exchange

In Section 12.1, it is written that most cells of a plant have at least a part of their surface in contact with air. The arguments in favor of this statement include all except:
1. Flattened leaves
2. Closely packed parenchyma in most regions
3. Presence of lenticels
4. Mostly dead cells in the interior

The enzymatic machinery to partially oxidize glucose without the help of oxygen is present in:
1. All living organisms
2. All prokaryotes only
3. Prokaryotes and obligate anaerobes only
4. Facultative and obligate anaerobes only

Sucrose is converted into glucose and fructose by the enzyme:

How many ATP molecules are directly synthesized in glycolytic pathway from one glucose molecule?

What is the metabolic fate of pyruvate?
1. It is the end product of glycolytic pathway
2. It is reduced to acetyl CoA in the presence of oxygen
3. It depends on the cellular needs
4. It is decarboxylated in the cytosol

Based on the information given in Section 14.3 of your NCERT textbook, can you identify the chemical reaction catalyzed by the enzyme alcohol dehydrogenase?
1.${\mathrm{C}}_{12}{\mathrm{H}}_{22}{\mathrm{O}}_{11}+{\mathrm{H}}_2\mathrm{O}\to 2{\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6$
2.${\mathrm{CH}}_3{\mathrm{COCOO}}^{-}+{\mathrm{H}}^{+}\to {\mathrm{CH}}_3\mathrm{CHO}+{\mathrm{CO}}_2$
3. ${\mathrm{CH}}_3\mathrm{CHO}+\mathrm{NADH}+{\mathrm{H}}^{+}\to {\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}+{\mathrm{NAD}}^{+}$
4. None of these

The maximum concentration of alcohol in beverages that are naturally fermented is about:

Pyruvate is transported into the mitochondria by:
1. Simple diffusion
2. Facilitated diffusion
3. Active transport
4. Either 2 or 3, depending on the availability of oxygen