Instructions for Dissection for Study of Central Nervous System of Cockroach
Cuts open the cockroach as instructed earlier. Remove the alimentary canal and remaining fate bodies and observe the ventral nerve cord. Trace the three pairs of thoracic ganglia by pulling apart the legs and removing the muscles. Remove the viscera, fat bodies and trachea and observe the abdominal ganglia. Locate the brain which is situated in the head, in between two eyes and below the epicranium. Hold the head in hand and take cuts onto lateral sides outside the antennae. Insert the angular scissor and cut the epicranium transversely. Lift up the front part of head capsule and remove it by scraping with arrow headed needle and observe the bilobed brain. Cut open the neck and part of head capsule up to the brain and separate them from the brain. With the help of forceps find out the hard part of occipital ring, break it and trace the sub-oesophageal ganglion. Mount the system on black back-ground and observe the brain, sub-oesophageal ganglion, thoracic ganglia and abdominal ganglion, thoracic ganglia and abdominal ganglia.