Question

Mitochondrial marker enzyme is
a) Pyruvate dehydrogenase
b) Aldolase
c) Amylase
d) Succinate dehydrogenase

Answer 1

Hint: Mitochondria is the membrane bound organelle. Mitochondria is the powerhouse of the cell. It is used in the production of ATP molecules which are used for the energy production in the cell. It generates the chemical energy of the cell.

Complete answer:
Succinate dehydrogenase is an essential mitochondrial marker enzyme. It is very useful in connecting the oxidative phosphorylation and the electron transport chain. It provides a variety of the electrons needed in the respiratory chain process taking place in the mitochondria.

Additional Information: The mitochondria consist of a double membrane- the outer membrane and the inner membrane. The outer membrane covers the whole cell. Between the two membranes is a space present which is known as the intermembrane space. The outer membrane is permeable in nature whereas the inner membrane is not much permeable. The inner membrane is involved in the electron transport and also in the transportation of the ATP formed. The inner membrane surrounds the mitochondrial matrix where the process of the citric acid cycle takes place. The mitochondrial marker enzymes are enzymes that are found in the mitochondria. They are present in the mitochondrial matrix, inner mitochondria, and the outer mitochondria. They are also present in the inter-membranous space.
So, the answer is ‘succinate dehydrogenase’.

Note: The mitochondrial matrix enzymes present are citrate synthase, NAD+ malate dehydrogenase, NAD+ glutamate dehydrogenase, adenylate kinase, cytochrome- c reductase, succinate dehydrogenase, monoamine oxidase, and kynurenine hydroxylase. These enzymes are present either in the mitochondrial matrix or inner or outer membrane of the mitochondria, even the intermembrane space contains enzymes.