Reflex action is a rapid, automatic action carried out without the intervention of the will of the animal. It is independent of the will of the animal. Marshall Hall first observed such action in the year 1833. During reflex action the impulse travels through a path known as reflex arc. A simple reflex arc (monosynaptic) involves a sensory or afferent [...]
There are twelve pairs of cranial nerves in man. They are numbered by Roman numeral I to XII. A cranial nerve arises from the brain by two roots, a dorsal and a ventral root. These two roots do not unite but appear like separate nerves. The cranial nerves are generally medullated (having a myelin sheath). The following table shows the [...]
The Nervous System of Cockroach can be Divisible into Three Parts: (i) The central nervous system, (ii) Peripheral nervous system, (iii) Visceral or sympathetic nervous system. The central nervous system of cockroach (Fig. 1.2) consists of the supra-oesophageal or cerebral ganglia, sub-oesophageal ganglia and circum oesophageal connectives in the head and a double ganglionated ventral nerve cord in the thorax [...]