If 5 ml of 20% ethanol is mixed with 25 ml of 80% ethanol, the resulting solution will approximately be (1) 50% ethanol (3) 100% ethanol (2) 70% ethanol (4) 80% ethanol
If you were to take 1.0 ml of a solution of HCl with a pH of 4.0 and add it to 9.0 ml of distilled water, what would be the pH of the final solution? (1) The pH would remain unchanged. (2) The pH would rise to 5.5. (3) The pH would rise to 5.0. … Read more
What will be the required volumes of 1N HCl and 4N NaOH to prepare one litre solution of pH 77 (1) 500 ml, 500 ml. (3) 600 ml, 400 ml (2) 800 ml, 200 ml (4) 200 ml, 800 ml To prepare 1 litre of a solution with pH = 7 using 1N HCl and … Read more
How many millilitres of 0.05 N HCI are required to neutralize eight grams of NaOH? (1) 5000 (2) 4000 (3) 4500 (4) 5050 To determine the volume of 0.05 N HCl required to neutralize 8 g of NaOH, follow these steps: Step 1: Calculate Moles of NaOH Molecular weight of NaOH = 40 g/mol Moles … Read more
Match enzymes of TCA cycle in Group I with that of their products listed in Group II. Group I P. Isocitrate dehydrogenase Q. Succinate dehydrogenase R. Fumarase S. x-Ketoglutarate dehydrogenase Group II 1. x-Ketoglutarate 2. Succinyl CoA 3. Fumarate 4. Malate (1) P-1, Q-2, R-4, S-3 (2) P-3, Q-1, R-2, S-4 (3) P-2, Q-4, R-3, … Read more
Among the following bonds where rotation is not allowed in a peptide chains? (1) ψ (2) ω (3) x (4) φ In a peptide chain, rotation is restricted due to partial double-bond character of certain bonds. Let’s analyze each option: 1. ψ (Psi) angle – Rotation Allowed ✅ This is the Cα–C bond (between the … Read more
Arrange the three residues, glycine, phenylalanine and proline, in the decreasing order of backbone flexibility (1) Gly > Phe > Pro (2) Pro > Gly > Phe (3) Phe > Pro > Gly (4) It is not possible to comment Backbone flexibility in amino acids depends on the torsional freedom of the main chain (Φ, … Read more
In a polypeptide chain, a cis-to-trans rearrangement of two consecutive proline residues can be achieved by rotating the: (1) O angle to 10° (2) w angle to 180° (3) Ψ angle to 0° (4) x angle to 60° In a polypeptide chain, cis-to-trans isomerization primarily involves rotation around the peptide bond (ω angle). ω (omega) … Read more
The measured values of main chain torsion angles of a residue in a polypeptide has values (Φ=+50, Ψ=+60). What type of secondary structure is it most likely to be present in?
(1) Left-handed a-helix
(2) Right-handed a-helix
(3) Type II ẞ-turn
(4) Parallel B-sheet
In peptides the values of dihedral angle phi (D) is based on rotation around (1) N-Ca bond (2) Ca -C’ bond (3) C’-N bond (4) N-H bond The phi (φ) angle in peptides is defined as the dihedral angle around the N–Cα bond. This angle is measured between the plane formed by the C’ (of … Read more