2.82 Communication

• The nerve impulse is carried along inside the nerve from the cell body to the Synaptic Knob where it connects to the muscle.
• In mammals the axon is surrounded by a Schwann Cell which contains a great deal of fat.
• The Myelin Sheath increases nerve conduction.
• The endocrine gland produces a chemical known as a hormone.
• Hormones can be proteins or steroids eg. Adrenal Gland.