Question

A) What do you understand by the term apoenzyme?
B) Distinguish between isoenzyme and coenzyme.
C) Distinguish between apoenzyme and coenzyme.
D) Differentiate enzyme and isoenzyme.

Answer 1

Hint: Enzyme,a material that functions in living organisms as a catalyst,which controls the rate at which the chemical reactions proceed without altering the process itself.The enzymes regulate the chemical reactions which occur within all the living organisms.

Complete step by step answer:
A) What do you understand by the term apoenzyme?
The biochemical process is speeded up by the enzymes.Those enzymes which do not require a cofactor to speed up the process is called simple enzyme.Those enzymes which require a cofactor is called conjugate enzyme.The two parts of the conjugate enzyme are cofactor and apoenzyme.The former is the non-protein part whereas the later is the protein part.Cofactor may be organic or inorganic.Apoenzyme is an inactive enzyme that becomes active(holoenzyme) after combining with organic or inorganic cofactor.
B)Distinguish between isoenzyme and coenzyme.

	ISOENZYME	COENZYME
Definition	The enzymes that exist in a variety of different types are called Isoenzymes or Isozymes and differ chemically,immunologically and electrophoretically from each other.	Many substratum reactions are only stimulated by enzymes in the presence of a particular organic non protein molecule called a coenzyme.To form holoenzyme,coenzyme combies with apoenzyme.The coenzymes are known to be co-substrates as well.
Occurrence	In mammals,amphibians,birds,Insects,plants and unicellular species Isoenzymes are found in serum and tissues	Coenzymes are organic heat stable,dialyzable non protein molecules and enzyme prosthetic groups.
Characteristics/function	The distinction between certain isozymes is due to variation in enzyme quaternary structure example:in five isozymic form,lactate dehydrogenase exists.	Typically their function is to accept atoms or groups from a substrate and transfer them to other molecules.They are less precise than enzymes and in variety of different reactions same coenzyme may behave as such

D)Distinguish between apoenzyme and coenzyme

	APOENZYME	COENZYME
Meaning	The protein part of the holoenzyme or conjugate enzyme is apoenzyme.	The non protein part of coenzyme combines with the apoenzyme to form conjugate or holoenzyme.
Size	larger	smaller
Specific	Specific for an enzyme	This is non specific as it can act as a cofactor to number of enzymes carrying a specific type of reaction
Group transfer	Does not allow	Allow
Function	It acts as a catalyst	In addition to bringing interaction between substrate and enzyme,it assists in extracting a chemical reaction product

D)Differentiate enzyme and isoenzyme

	ENZYME	ISOENZYME
Meaning	A globular protein that catalyzes a biological chemical reaction.It speeds up the reaction rate.	These enzymes have a similar function but differ in structural and biochemical properties.

Note:
Coenzymes are usually inorganic compounds such as metal ions like Fe and Zn. Enzymes usually have a suffix of -ase after the name. Some common enzymes include DNA polymerase(unravels DNA), trypsin , pepsin (digestive enzymes) and amylase (present in mouth for digestion of carbohydrates.