The most important property of an enzyme is its

Which one statement regarding isoenzymes is correct?

The following reaction depicts the activity of a particular class of enzymes:
$X-Y$ attached to $C-C$ (Substrate) $\xrightarrow{E}$ $X-Y$ + $C=C$ (Product)
Identify the enzyme class '$E$' from the following options:

Water-soluble and colloidal catalysts made of proteins are:

Inhibition of Succinic dehydrogenase enzyme by malonate is a classical example of.

What does $Q$ represent in the given figure?