Final answer:
The innermost layer of the meninges, delicate and adjacent to the brain tissue, is the pia mater.
Step-by-step explanation:
The innermost layer of the meninges, delicate and adjacent to the brain tissue, is the pia mater. The meninges are three-layered membranes that enclose and protect the brain and spinal cord, and the pia mater is the thin fibrous membrane that directly contacts and covers the brain and spinal cord. It follows the convolutions of the cerebral cortex and fits into other grooves and indentations.
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