Consider the following statements.

(1) Myelinated axons have Schwann cells.

(2) Schwann cells of myelinated axons produce myelin sheath.

(3) Schwann cells are absent in non-myelinated axons.

(4) Schwann cells of non-myelinated axons do not produce myelin sheath.

(1), (2) and (3) are true. (3) is false.

(1) Myelinated axons have Schwann cells.

(2) Schwann cells of myelinated axons produce myelin sheath.

(3) Schwann cells are present in non-myelinated axons. Unmyelinated nerve fibre is also enclosed by a Schwann cell that however does not form a myelin sheath around the axon, and is commonly found in autonomous nervous system.

(4) Schwann cells of non-myelinated axons do not produce myelin sheath.