Zoology · Ch 4 — Organ and Organ Systems in Animals
The Nervous System
The Nervous System
The frog's nervous system is organised into a central nervous system (brain and spinal cord), a peripheral nervous system of 10 pairs of cranial nerves and 10 pairs of spinal nerves, and an autonomic nervous system (split into sympathetic and parasympathetic divisions) that controls involuntary activity of the internal organs. The brain sits in the cranial cavity, wrapped in two membranes (piamater and duramater), and is divided into three regions. The forebrain (prosencephalon), the largest and most anterior part, includes a pair of olfactory lobes (with a small internal olfactory ventricle) fused posteriorly, the paired cerebral hemispheres (telencephalon), and the diencephalon. The midbrain (mesencephalon) consists of two large optic lobes with their own optic ventricles. The hindbrain (rhombencephalon) has a narrow cerebel …
What this figure shows. Dorsal and ventral views of the brain labelling the olfactory lobes, cerebral hemispheres, diencephalon, pineal body, optic lobes, cerebellum, medulla oblongata, optic chiasma, infundibulum and pituitary body, plus a schematic of the internal cavities - olfactory ventricle, lateral ventricle, foramen of Monro, third ventricle, optic ventricle and fourth ventricle. …