Enzymes and vitamins

28 questions on Enzymes and vitamins from the Biomolecules chapter: 6 NEET level, 11 JEE Main, 11 JEE Advanced. Each one opens with its answer and solution.

• Most enzymes, which act as biological catalysts, are chemically NEET level
• The enzyme that hydrolyses cane sugar (sucrose) into glucose and fructose is NEET level
• Prolonged deficiency of vitamin C in the diet causes NEET level
• Which one of the following vitamins is fat soluble? NEET level
• The vitamin whose molecule contains the metal cobalt is NEET level
• The enzyme urease catalyses the hydrolysis of NEET level
• An enzyme E catalyses the reaction S <=> P at constant temperature. Which statement is correct? JEE Main level
• An uncatalysed reaction has E_a = 75 kJ mol^-1 and the enzyme-catalysed reaction has E_a = 50 kJ mol^-1. Assuming the same pre-exponential factor and T = 300 K ... JEE Main level
• Which of the following enzyme-substrate or enzyme-reaction pairs is correct? JEE Main level
• In an enzyme-catalysed reaction with a fixed amount of enzyme, the rate is measured at increasing substrate concentration [S]. Which description is correct at t... JEE Main level
• Which pairing of a vitamin with the deficiency disease it causes is correct? JEE Main level
• Water soluble vitamins are generally excreted in urine and must be supplied regularly in the diet. Which water soluble vitamin is the exception, being stored in... JEE Main level
• Which statement about cofactors is correct? JEE Main level
• A human enzyme has maximum activity at about 37 degC. What happens to its activity when the temperature is raised well above the optimum? JEE Main level
• A competitive inhibitor of an enzyme JEE Main level
• Which of the following vitamins are fat soluble? JEE Main level
• Select the correct statements about enzymes. JEE Main level
• For a reaction at T = 310 K the uncatalysed activation energy is 100 kJ mol^-1 and the activation energy with an enzyme is 40 kJ mol^-1. Assuming equal pre-expo... JEE Advanced level
• The reaction S -> P is exothermic with Delta H = -30 kJ mol^-1. Its uncatalysed forward activation energy is 90 kJ mol^-1. An enzyme lowers the forward activati... JEE Advanced level
• For an enzyme-catalysed reaction with fixed enzyme concentration, the initial rate was 5 mu M s^-1 at [S] = 0.1 mM, 10 mu M s^-1 at [S] = 0.2 mM, 98 mu M s^-1 a... JEE Advanced level
• Two inhibitors are tested on an enzyme. With inhibitor X the rate at very high [S] reaches the same plateau as without inhibitor, although a higher [S] is neede... JEE Advanced level
• Match List I (vitamin) with List II (deficiency disease). List I: P = vitamin B1, Q = vitamin B12, R = vitamin K, S = vitamin D. List II: 1 = rickets, 2 = delay... JEE Advanced level
• Assertion (A): A person who gets very little exposure to sunlight may develop rickets (or osteomalacia in adults) even when the diet is otherwise adequate. Reas... JEE Advanced level
• At equilibrium, K = k_f/k_r for S <=> P. An enzyme raises k_f by a factor of 10^4 at constant temperature. By what factor does it change k_r, and what is the ne... JEE Advanced level
• An enzyme catalyses S <=> P with Delta G = -12 kJ mol^-1 at 300 K. Select the correct statements. JEE Advanced level
• Select the correct statements. JEE Advanced level
• Select the correct statements about the effect of temperature and pH on enzymes. JEE Advanced level
• An enzyme-catalysed reaction has E_a = 80 kJ mol^-1 without the enzyme and 50 kJ mol^-1 with it, at 300 K. Take R = 8.314 J mol^-1 K^-1, equal pre-exponential f... JEE Advanced level