The tough protective layer of brain is ____ (i) ____ and inner highly vascularized protective layer is ___ (ii) ___.

	(i)	(ii)
1	pia mater	dura mater
2	dura mater	pia mater
3	dura mater	arachnoid
4	pia mater	sub dural space

Dura mater is the most superficial of the three spinal meninges is a thick strong layer composed of dense irregular connective tissue.

Arachnoid mater is the middle layer with spider’s web arrangement of delicate collagen fibers and some elastic fibers.

Pia mater is the innermost meninx which is a thin transparent connective tissue layer that has many blood vessels (highly vascular) that supply oxygen and nutrients to the spinal cord.