Question

Pharyngeal ganglion in leech is a part of ________.

• A. digestive system
• B. nervous system
• C. respiratory system
• D. circulatory system

Answer 1

The correct option is B nervous system

Ganglions are a cluster of nerve cells. Leech's body is divided into 32 segments, so it has its own ganglia in each segment which controls their respective segments. The Central Nervous System of leech consists of a nerve ring and a paired ventral nerve cord. The nerve ring surrounds the pharynx and is formed of suprapharyngeal ganglion (brain), circumpharyngeal connective and subpharyngeal ganglion. Subpharyngeal ganglion is formed by the fusion of four pairs of ganglia.