Question

Read the following statements:
I. Photosynthesis takes place within the chloroplasts of the eukaryotes, whereas the breakdown of complex molecules to yield energy takes place in the cytoplasm and in the mitochondria.
II. Photosynthesis takes place within the chloroplasts of the prokaryotes, whereas the breakdown of complex molecules to yield energy takes place in the cytoplasm and in the mitochondria.
III. All living organisms retain the enzymatic machinery to partially oxidise glucose without the help of oxygen. This breakdown of glucose to pyruvic acid is called glycolysis.
IV. All living organisms retain the enzymatic machinery to completely oxidise glycerol without the help of oxygen. This breakdown of glycerol to citric acid is called glycolysis.
The correct choice is:

• A. I and III are correct
• B. II and IV are correct
• C. I is correct whereas III is incorrect
• D. II is correct whereas IV is incorrect

Hint:

Remember: Glycolysis is the universal pathway in all organisms for glucose breakdown (anaerobic), while mitochondria are specific to eukaryotes for aerobic respiration.

Answer 1

The Correct Option is A

Step 1: Evaluate statement I.
In eukaryotes, photosynthesis occurs in the chloroplasts, while breakdown of glucose (respiration) occurs partly in the cytoplasm (glycolysis) and partly in the mitochondria (Krebs cycle, ETC). Thus, statement I is correct.
Step 2: Evaluate statement II.
Prokaryotes do not have chloroplasts. Photosynthesis in prokaryotes (like cyanobacteria) occurs in specialized membranes, not in chloroplasts. So statement II is incorrect.
Step 3: Evaluate statement III.
Glycolysis occurs in all living organisms. It partially oxidizes glucose to pyruvate without oxygen. This is a universal pathway. Hence, statement III is correct.
Step 4: Evaluate statement IV.
Glycolysis refers specifically to the breakdown of glucose, not glycerol. Glycerol metabolism follows a different pathway. Thus, statement IV is incorrect. Therefore, the correct choice is (I and III). Final Answer: \[ \boxed{\text{(A) I and III are correct}} \]