BIO310H5 Lecture Notes - Lecture 4: Reflex Arc, Motor Neuron, Sensory Neuron
Document Summary
Main functions of neurons can be divided into three categories: sensory reception, central processing and motor output. In simple animals, sensory receptors and neurons controlling motor output are distributed throughout the organism (ex. In the cns the cell bodies of neurons are located close to one another, receptors and effectors in the rest of the body (periphery) connect to the cns by long axons. Information flows into nervous system from sensory receptor neurons and out by motor neurons which produce responses in effectors such as muscles and glands (ex. Polysynaptic reflex arc contains one interneuron intervening between the sensory and motor neurons. Simplest nervous system consist of axons distributed in networks (carry signals in all directions) called nerve nets. The axons make synaptic contacts at points where they intersect, so a stimulus applied to one part of a jellyfish produces a response that spreads in all directions away from the point of stimulation.
