Which of the following statements regarding mitochondria is incorrect?
- Inner membrane is convoluted with infoldings
- Mitochondrial matrix contains single circular DNA molecule and ribosomes
- Outer membrane is permeable to monomers of carbohydrates, fats and proteins
- Enzymes of electron transport are embedded in outer membrane
Answer
(4) Enzymes of electron transport are embedded in outer membrane
Solution
As per NCERT, the inner membrane of mitochondrion forms a number of infoldings called cristae (1 correct); the matrix possesses a single circular DNA molecule, a few RNA molecules, ribosomes (70S) (2 correct); the outer membrane is porous and permeable to small molecules (3 correct).
The electron transport system is located on the inner mitochondrial membrane, not on the outer membrane.
∴ Statement (4) is incorrect.
Answer: (4)