We learn that the equator is a line around the wide waist of the world. Pleasure cruisers often make a great toâdo about crossing this line on the ocean. Any passenger who owns up to the fact that this is his first crossing may be put through ceremonies such as walking the plank and other merry goingsâon.
Ectoderm â Outer or External Layer â differentiates into the nervous system, epidermis, and the outer part of the integument system â forms the central nervous system, the lens of the eye, cranial and sensory, the ganglia and nerves, pigment cells, head connective tissues, the epidermis, hair, and mammary glands.
Rating Newest Oldest. Best Answer: The central nervous system is the brain and spinal cord. The peripheral nervous system includes the 12 cranial nerves and 31 spinal nerves that exit the central nervous system and branch to all the muscles and organs.The enteric nervous system is composed of nerves that control the gastrointestinal tract, which is also their location.he peripheral nervous system includes the 12 cranial nerves and 31 spinal nerves that exit the central nervous system and branch to all the muscles and organs. The enteric nervous system is composed of nerves that control the gastrointestinal tract, which is also their location.