human anatomy nerves

responsible for reflexes which are the quickest reactions to a stimuli. 31 pairs of spinal nerves

• the anterior rami of most spinal nerves form nerve plexus on both sides of the body
• the plexus are the cervical plexus, brachial plexus, lumbar plexus, sacral plexus.

is the area of skin innervated by the cutaneous branches of a single nerve.

the CNS communicates with the peripheral body structures though these, it consists of a tract and a nucleus.

primary, secondary, and sometimes tertiary neurons.

upper motor and lower motor neurons.

• direct pathway- conscious control of skeletal muscle activity.
• indirect pathway- unconscious control of skeletal muscle activity.

• are rapid automatic involuntary reactions of muscles or glands to a stimulus.
• monosynaptic- sensory axons synapse directly on motor neurons whose axons project to the effector.
• polysynaptic- more complex pathway that exhibit a number of synapses involving interneurons within the reflex arch.

• 2 divisions (of things we cant control)-
• sympathetic nervous system- fight or flight short pregangion, long post ganglion.
• parasympathetic nervous system- rest and digest. long preganglion short post ganglion.

temprature, pain, touch, stretch, and pressure

gustation, olfactory, vision, equilibrium, and audition.

structures that detect stimuli, can be structurally complex like the eye or very simple (dendrite endings in the nose)

the smaller the receptive field the more sensitive and precise the receptor.

found in skin or mucous membrane such as nasal or oral cavities.

found in the walls of visceral

found in muscles, tendons and joints

they include receptors for chemicals, temperature, pain, touch, propriorection, and pressure.

they respond to chemicals, temperatures and pressure.

detects tissue damage and pain.