Mdcat-past-papers Quiz

2341. The term feedback refers to:

Enzymes remain unaffected
Product accelerates the production of enzymes
Enzyme is inhibited by product
both b & c are correct

2342. At temperature higher than optimum, enzyme activity decreases due to:

Saturation
Denaturation
Composition
inhibition

2343. Considering enzyme action minimum temperature is the term used when:

Enzymes start denaturing
enzyme work at their best
enzymes become hyperactive
inactive enzyme getting reactivated

2344. Most enzymes work best at the following temperature:

30°C
50°C
40°C
20°C

2345. In term of enzyme action, 'maximum temperature' refers to a temperature at which:

Enzymes starts to denature
Enzymes work best
Enzymes are reactivated
Enzymes start to denature

2346. The type of inhibition in which inhibitor has no structural similarity to substrate and combines with enzyme at site other than active site is called:

Irreversible inhibition
Competitive inhibition
Non-competitive inhibition
Reversible inhibition

2347. The inhibitors that binds tightly and permanently to enzymes and destroy their globular structure and catalytic activity are:

Reversible inhibition
Irreversible inhibition
Competitive inhibition
Non competitive inhibition

2348. Enzyme succinate dehydrogenase converts succinate into:

Malate
Malonic acid
Citrate
Fumarate

2349. The competitive inhibitors have structural similarity with:

Active site
Substrate
Binding site
Co-enzyme

2350. Which of following is an example of competitive inhibitors:

Glucose
Fumarate
Succinic acid
Malonate

2351. If inhibitor bind to another site of enzyme rather than the active site then it is referred as:

Competitive Inhibitor
NonCompetitive Inhibitor
Irreversible
Allosteric

2352. What is common in both competitive and non-competitive inhibitors:

Competitive
Reversible
Allosteric inhibitors
Irreversible

2353. A student of chemistry mistakenly engulfed the toxic compound "A" which was a potent inhibitor of certain enzyme. He was immediately brought to hospital where Dr. Injected intravenously substrate "B" to minimize the toxic effect of compound A. His life was saved from serious damages. The treatment method shows that the compound A was:

Temperature sensitive
Competitive reversible
Irreversible
Non competitive reversible

2354. Non-competitive inhibitor molecules have:

A similar structure to the normal substrate molecule
A quite different structure from the substrate molecule
A different conformation but fit into the active site
A similar conformation but does not fit into the active site

2355. Competitive inhibitors compete with?

Enzyme
Substrate
Product
Coenzyme

2356. Competitive inhibitors are:

Homologous to substrate
Analogous to substrate
Smaller than substrate
Larger than substrate

2357. They are inhibitors of key enzymes in the nervous system

Calcium and Potassium
Hexokinase and glucose
Substrate and activators
Magnesium and manganese

2358. Penicillin blocks the active sites of an enzyme that many bacteria use in making cell wall. It is an example of:

Competitive Inhibition
Incompetitive inhibition
Feedback inhibition
radiation effect

2359. The structure of an enzyme is altered by:

Irreversible inhibition
Reversible inhibition
Competitive inhibition
Non competitive inhibition

2360. Chemical substance that can react with an enzyme faster than real substance and without producing a product is:

Accelerator
Inhibitor
Co-enzyme
Activator