Enzyme Catalysis

Q.

What is competitive inhibition?

Q.

What is the end product of protein digestion?

Q.

Inhibition of succinic dehydrogenase by malonate is an example of

1. Competitive inhibition

2. Non-competitive inhibition

3. Negative feedback

4. Allosteric inhibition

Q. Which one of the following statement is incorrect about enzyme catalysis?

1. Enzymes are denaturated by ultraviolet rays and at high temperature
2. Enzymes are least reactive at optimum temperature
3. Enzymes are mostly proteinous in nature
4. Enzyme action is specific

Q.

What is end product inhibition?

Q.

How do you know if an enzyme is denatured?

Q.

What are enzymes made of?

Q. Enzyme-catalysed reactions have the order

1. one at low concentration of substrate and two at high concentration of the substrate
2. one of high concentration of the substrate and two at low concentration of the substrate
3. one at low as well as high concentrations
4. two at low as well as high concentrations

Q.

The proteins which are insoluble in water are

1. Both (a) and (b)

2. None of these

3. Fibrous proteins

4. Globular proteins

Q. Enzymes that utilize ATP in phosphate transfer, require an alkaline earth metal (M) as the cofactor. M is:

1. $Ca$
2. $Be$
3. $Sr$
4. $Mg$

Q.

Which types of metals make the most efficient catalysts?

Q. Which one of the following statements is not correct?

1. The value of equilibrium constant is changed in the presence of a catalyst in the reaction at equilibrium.
2. Enzymes catalyse mainly bio-chemical reactions.
3. Catalyst does not initiate any reaction.
4. Coenzymes increase the catalytic activity of enzyme.

Q.

What are enzymes ? Write in brief the mechanism of enzyme catalysis ?

Q. Identify the catalyst promoter and poison in the following reaction
N2(g)+3H2(g) ------> 2NH3(g)

Q.

Does pH affect cellular respiration?

Q.

Can a denatured enzyme be renatured?

Q.

Consider the reaction:Cl2(aq) + H2S(aq) → S(s) +2H+(aq) +2Cl-(aq)The rate equation for this reaction is rate =k[Cl2][H2S] Which of these mechanisms is/areconsistent with this rate equation?

A. Cl2 + H2S → H+ + Cl- +Cl+ + HS-(slow) cl+ + HS- → H+ +Cl- + S (fast)

B. H2S ⇔ H+ + HS-(fast equilibrium) Cl2 + HS- → 2Cl- + H+ + S (slow)

1. A only

2. B only

3. Both A and B

4. Neither A nor B

Q.

Pancreatic Lipase acts upon

1. Triglycerides

2. Glycogen

3. Polypeptides

4. Disaccharides

Q.

If A and B are two different chemical species undergoing 1st order decomposition with rate constant Ka and Know which are in the ratio 3:2 in magnitude. If the initial concentration of A and B are in the ratio 3:2 .What would be the concentration of A and B after three half lives of A

Q. A catalyst in finely divided form is the most effective, because :

1. less surface area is available
2. more active sites are formed
3. more energy get stored in the catalyst
4. none of these

Q. Which of the following is correct for chemical adsorption?

1. Increases with an increase in temperature
2. First increases, then decreases with an increase in temperature
3. Decreases with an increase in temperature
4. First decreases, then increases with an increase in temperature

Q. What names apply to chemical species corresponding to locations 1 & 2 on this reaction coordinate diagrams?

1. Location 1 - Reaction intermediate Location 2 - Activated complex
2. Location 1 - Activated complex Location 2 - Intermediate
3. Location 1 - Reaction intermediate Location 2 - Intermediate
4. Location 1 - Activated complex Location 2 - Activated complex

Q. why does chemical adsorption need high activation of energy

Q.

Which of the following reasons enable a catalyst to increase the rate of a chemical reaction?

1. Providing energy to the moleucules

2. Increasing the temperature of the reaction mixture

3. Increasing activation energy

4. Lowering the activation energy

Q. A circular plasmid of 10, 000 base pairs (bp) is digested with two restriction enzymes A & B, to produce a 3000 BP & 2000 bp bands when visualised on an agarose gel. When digested with one enzymes at a time, only one band is visible at 5000 bp. If the first site for enzyme A(A1) is present at the 100th base, in order in which the remaining sites (A2, B1, B2) are present in it A) 3100, 5100, 8100 B) 8100 3100, 5100 C) 5100, 3100, 8100 D) 8100, 5100, 3100

Q.

Which of the following statements is not true about enzyme inhibitors?
(a) Inhibit the catalytic activity of the enzyme
(b) Prevent the binding of substrate
(c) Generally a strong covalent bond is formed between an inhibitor and an enzyme
(d) Inhibitors can be competitive or non-competitive

Q. 46. In the cell reaction, Zn (s)+Cu2+(aq)~>Zn2+(aq)+Cu (s) , the concentration of Cu2+ is doubled. E^° cell will not change why

Q.

The inorganic catalyst attached to an enzyme is called

1. Apo-enzyme

2. Lysozyme

3. Activator

4. Inhibitor

Q.

Name the following:

An antiseptic substance present in tears.

Q.

1. True
2. False