Which enzyme acts as a marker enzyme for peroxisomes by catalyzing the decomposition of toxic hydrogen peroxide into water and oxygen?
Answer and explanation
Correct answer: A. Catalase
- Step 1: Peroxisomes contain flavin-dependent oxidases that transfer electrons to oxygen, producing dangerous hydrogen peroxide: .
- Step 2: To protect the cell from oxidative damage, peroxisomes contain large quantities of the heme enzyme catalase.
- Step 3: Catalase rapidly catalyzes the disproportionation reaction: .
Answer
Catalase.
Why not the others: Cytochrome c oxidase is Complex IV of the mitochondrial respiratory chain; Acid phosphatase is a classic lysosomal marker enzyme; Succinate dehydrogenase is a marker enzyme of the inner mitochondrial membrane (Complex II).
Practise more Cell Structure and Function.
Free questions with an explanation for every one, and full timed NEET UG mock tests.
More Cell Structure and Function questions
- Which of the following cellular organelles is enclosed by a single unit membrane and is rich in hydrolytic acid hydrolases?
- According to the fluid mosaic model proposed by Singer and Nicolson (1972), what is the primary state and arrangement of the lipid bilayer?
- Which component of the bacterial cell envelope determines cell shape and prevents the bacterium from bursting or collapsing in a hypotonic m…
- What is the structural organization of microtubules in the eukaryotic cilia and flagella axoneme?
- Which of the following organelles is directly involved in the synthesis of lipids, phospholipids, and steroid hormones in animal cells?
- In eukaryotic plant cells, what is the composition of the middle lamella that cements adjacent cell walls together?