Assertion: It is logical to infer that the ancestor of all living organisms today made ATP by glycolysis.
Reason: The enzymes responsible for glycolysis have been observed in nearly every prokaryote and eukaryote.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
3. If the assertion is true but the reason is false
4. If both the assertion and reason are false

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: