Neurotransmitters EXCITATORY - closer to action potential, or causes action
INHIBITORY - moves neuron further from action potential

Some examples of neurotransmitters are acetylcholine, monoamines, amino acids, and neuropeptides.

Depression is caused by an imbalance of neurotransmitters, and many drugs are created to imitate the effects of them (ie. Prozac, Zoloft)

THE RELEASE OF A NEUROTRANSMITTER
When action potentials reach the end of an axon, calcium channels open and allow a swell of calcium in. After the neurotransmitter binds to the calcium, it will either be destroyed in the synaptic cleft or be taken back to surrounding neurons.

Parasympathetic vs. Sympathetic Parasympathetic is UNDER NORMAL CONDITIONS
Sympathetic is UNDER STRESS OR EMERGENCY (fight or flight response)

The Peripheral Nervous System The nervous system active in everywhere else of the body besides the brain and spinal cord. The part that exercises the motor functions.

It is divided into the SOMATIC (conscious activities) and AUTONOMIC (unconscious activities) systems.

The Central Nervous System Consists of the brain and spinal cord. It uses both gray and white matter to protect the nerves, which are also covered in meninges.

Chapter 10: The Senses
Touch FREE NERVE ENDINGS respond to warm and cold temperature
MEISSNER'S CORPUSCLES respond to light touch usually picked up by hairs
PACINIAN CORPUSCLES respond to heavy pressure, and are usually located in deeper tissues

Sound The Outer Ear

sound waves are directed into it, and travels to the eardrum (or tympanic membrane) to make it vibrate

The Middle Ear

uses 3 auditory bones that feel the eardrum vibrate to mimic the vibrations and amplify them
the Eustachian tube connects the middle ear to the throat in order to equalize pressure

The Inner Ear

made of 2 labyrinths made of the OSSEOUS LABYRINTH of canals and the MEMBRANOUS LABYRINTH tube inside the osseous
the labyrinths end with the semicircular canals leading to the COCHLEA, which is the organ that "hears"

Sight The accessory organs of the eye are the eyelids, the eye muscles, and the lacrimal apparatus (produces tears to take to ducts)

SCLERA is a tough covering
CHOROID COAT contains the pigment for the eye
RETINA is the inner layers that continues to the optic nerve and contains receptors
VITREOUS HUMOR is jelly-like
CORNEA is the transparent covering
AQUEOUS HUMOR is the fluid between the iris and lens
IRIS is a pigmented layer that contains muscle that controls the size of the pupil
LENS is the layer that focuses the image on the retina

The retina uses two receptors:
RODS for black and white vision, indistinct images
CONES for color vision, for a more refined image

	Created by Courtney Merkel almost 9 years ago

Over the Nervous System and The Sense.