Biochemistry

Step 1: Understanding the reactions.
- Fehling's test (P) is used to test for reducing sugars, which reduce Cu to Cu in an alkaline solution.

- The Ninhydrin reaction (Q) is used to detect amino acids, which react with ninhydrin to form a blue or purple color.

- The Biuret reaction (R) is used to detect peptide linkages, as it forms a violet color in the presence of proteins or peptides.

- The Nitropusside reaction (S) is used to detect sulfhydryl groups, typically found in cysteine residues in proteins.

Step 2: Analyzing the options.
(A) P-1, Q-2, R-3, S-4: Incorrect — This option does not correctly match the reactions with the compounds they detect.
(B) P-3, Q-1, R-1, S-4: Incorrect — This option does not correctly match the reactions with the compounds they detect.
(C) P-2, Q-1, R-3, S-4: Correct — This correctly matches each reaction with the compound it detects: - Fehling's test detects reducing sugars (P-2), - Ninhydrin reaction detects α-amino acids (Q-1), - Biuret reaction detects peptide linkages (R-3), - Nitropusside reaction detects sulfhydryl groups (S-4).
(D) P-4, Q-1, R-2, S-3: Incorrect — This option does not correctly match the reactions with the compounds they detect.

Step 3: Conclusion.
The correct answer is (C) P-2, Q-1, R-3, S-4, as this correctly matches each reaction with the compound it detects.

Understanding the polymerization process:

When AMP molecules polymerize to form poly-(A), they connect through phosphodiester bonds. This condensation reaction releases one water molecule (H₂O, mass = 18) for each bond formed.

Calculating the molecular mass:

Step 1: Total mass of starting material

Starting with 100 AMP units: $ $

Answer: 32,818

Gravitropism refers to growth towards or away from gravity. Phototropism involves a response to light. Thigmotropism is a response to touch, seen in climbing plants. Chemotropism is the response to chemical stimuli, such as pollen tube growth.

Ethylene is a plant hormone that promotes fruit ripening by triggering enzymes involved in cell wall degradation, starch-to-sugar conversion, and pigment synthesis