Question

Assertion (A) In prokaryotes, mitochondria are absent.
Reason (R) In prokaryotes, mesosomes are present which help in respiration.

• A. If both A and R are true and R is the correct explanation of A
• B. If both A and R are true, but R is not the correct explanation of A
• C. If A is true, but R is false
• D. If A is false, but R is true

Answer 1

Answer: (B)

Both Assertion and Reason are true, but Reason is not true correct explanation of Assertion.
Mitochondria are absent in prokaryotes. Mesosomes are characteristic, circular to villiform shaped specialisation of cell membrane of bacteria that develop as ingrowths from the plasma membrane. It contains respiratory enzymes and is, therefore, often called chondroid. It is believed to be equal to mitochondrion of eukaryotes. However, respiratory enzymes are also present over the plasma membrane in prokaryotic cell.