Biology Mcqs

Which statement is incorrect about Lock and Key Model________________?

A. Specific enzyme can transform only a specific substrate
B. Active site of an enzyme is a non flexible structure
C. Active site does not change before during or even after the reaction
D. It explains the mechanism of every chemical reaction

The rate of reaction is directly proportional to the concentration of an enzyme which statement is incorrect in this respect_________________?

A. Increase in enzyme molecule increases the available active sites.
B. This relation is for unlimited time period with unlimited enzyme concentration
C. If the concentration is doubled the rate will become two fold.
D. None of these.

A group of ribosomes attached to mRNA is known as___________?

A. Polymer
B. Polypeptide
C. Polysomes
D. Monomer

If more substrate to already occurring enzymatic reaction is added more enzyme activity is seen because_____________?

A. There is probably more substrate present than there is enzyme.
B. There is probably more enzayme available than there is substrate.
C. There is probably more product present than there is either substrate or enzyme.
D. The enzyme substrate complex is probably failing to form during the reaction

Cellular organelles related with H2O2 are___________?

A. Glyoxisomes
B. Lysosomes
C. Peroxisomes
D. Ribosomes

A three dimensional dcavity bearing a specific charge by which the enzyme reacts with its substrate is called_________________?

A. Active site
B. Binding site
C. Catalytic site
D. Allosteric site

Which statement about enzyme is incorrect_________________?

A. Some of them consist solely of protein with no non protein part.
B. They catalyze a chemical reaction without being utilized.
C. All enzymes are fibrous Proteins.
D. They without their cofactor are called apoenzyme.

Centrioles are composed of ________ triplets of microtubules.

A. 3
B. 9
C. 10
D. 15

An activated enzyme consisting of polypeptide chain and a cofactor is called_______________?

A. Apoenzyme
B. Holoenzyme
C. Activated enzyme
D. Both b and c

A cofactor made of inorganic ion which is detachable is called__________________?

A. Prosthetic group
B. Coenzyme
C. Activator
D. Cofactor