Nervous System

Front 1

Receptors

Back 1

1) modified dentritic ending of sensory nerves, responds to specific kinds of stimuli

2) elaborate sense organ
ex) eye's retina, organ of Corti in the ear

A) has low threshold for a stimulus

B) only one kind of message sent to the CNS = Muller's doctrine of spcific nerve energies

3 major groups (anatomical)
1) Exteroceptors
2) Proprioceptors
3) Interoceptors

Front 2

Exteroceptor

Back 2

one of the groups of receptor

- receive direct stimulation from the environment
- receptors on the skin

eye, ear, nose, tongue, fingertips

Front 3

Proprioceptor

Back 3

- set up impulses resulting in restoration of stretched structure
-maintain posture, sense of position in space

muscles, tendons, areas surrounding joints

Front 4

Interoceptor

Back 4

- terminate in surfaces of blood vessels, internal organs

- involved in control of homeostatic responses of lungs, heart

Front 5

Effectors

Back 5

end structures in a reflex arc bringing about a specific response

muscles, glands, smooth muscle

-not a neural structure