4. Which of the following is correct:
(a) Cells of all living organisms have a nucleus.
(b) Both animal and plant cells have a well-defined cell wall.
(c) In prokaryotes, there are no membrane-bound organelles.
(d) Cells are formed de novo from abiotic materials.
Answer
All other statements are incorrect as cells of some organisms can lack a nucleus (e.g. RBC ), animal cells do not possess a cell wall and cells are formed from pre-existing cells. In prokaryotes, there are no membrane-bound organelles. Hence, the correct statement is (c).