Outside the brain and spinal cord there are aggregations of cell bodies of neurons called ganglia. There are two main types of ganglia. They are sensory and autonomic ganglia. A) Sensory ganglia These ganglia are present on the dorsal nerve roots of spinal nerves, where they are called dorsal nerve root ganglia or spinal ganglia. … Read more
Introduction of Spinal cord It is a whitish, long, dorso-ventrally compressed tube of nervous tissues. It is a part of the central nervous system that is posterior to the brain and enclosed within the vertebral column. It runs through the neural canal of the vertebral column which protects it from injuries. It shows two slight … Read more
multicellular, triploblastic, bilaterally symmetrical. first animals to have organ-system grade of body organization. body is dorsoventrally flattened so called flat worms. size varies from less than mm and more than 10-15 metres. mostly parasitic, few are free living and are found in water or damp soil. parasitic forms have hooks and suckers to stick to … Read more