solution.com

Q.11 Assertion–Reason Assertion (A): During aerobic respiration, one molecule of glucose yields about 38 ATP. Reason (R):ATP is formed as electrons pass through the electron-transport chain creating a proton gradient. Correct Answer: ✔ (b) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A). Explanation ✔ Assertion is true In prokaryotes: ~38 ATP In eukaryotes: ~36 ATP So the statement is generally considered true for basic textbook level. ✔ Reason is also true In ETS, electrons move through complexes, pumping protons → proton gradient → ATP formation by ATP synthase. ❌ But Reason is NOT the correct explanation The Reason explains how oxidative phosphorylation produces ATP, but it does not explain the total yield of 38 ATP from glucose. Therefore, both statements are correct but the reason does not directly explain the assertion. . Q.12. Assertion (A): Dedifferentiation allows some mature cells to regain the...

EVOLUTIONARY TRENDS There has been always a dispute among biologuts in tracing the possible origin of cells. Did early cells arise from a single first cell or did numerous first cells originale inde pendently, te. whether they evolved monophyletically, from a single common ancestral stock or polyphyletically, from several separate ancestral stocks Monophyletic versus Polyphyletic origin The proponents of monophyletism beiseve that cells are so complet that multiple origins of such complexities are statistically quite unlikely. They propose that all life started in a single place at a single time from a single cell which formed by lucky accident. They seek the support of homology argument that all cells are fundamentally so remarkably alike in chemical composition, in microscopic structure and in Function that a common origin from a single ancestry in clearly evident. The proponents of polyphyletism propose a probability argument in their own way They state that original cells coul...