3.3 Nervous System Flashcards
What is the nervous system?
A vast communication Network that coordinates and carries messages between all parts of the body.
Two main parts of the nervous system?
The central nervous system (CNS) and the peripheral nervous system (PNS)
Meninges
The protective membranes that surround the brain and spinal cord
Brain
A spongy and complex or organ comprised of more than 100 billion nerve cells. Part of the central nervous system
Three main parts of the brain?
Cerebrum, cerebellum, brainstem
Function of the cerebrum?
Manage nerve impulses, control most involuntary muscle contractions, interpret information gathered by senses, influence the foundation of personality emotions and attitudes.
Function of the cerebellum?
Located below and behind the cerebrum, the cerebellum adjust the motor impulses that control muscular coordination, body balance and posture
Function of the brain stem?
Located at the base of the brain, the brainstem is formed by bundles of nerves, it controls automatic body functions like heartbeat and breathing
PNS - Peripheral nervous system
A network of nerves and sense organs that branch out of the CNS and connect to other parts of the body
Autonomic nervous system
Part of the PNS, it controls all involuntary body processes like heartbeat and peristalsis (the rippling motion of muscles in the digestive tract)
Sense organs
Eyes, ears, nose, tongue and skin
Eyes
Vision organs that produce images by focusing light rays that are interpreted by the brain
Three layers of tissue in the eye?
Sclera, choroid, retina
Sclera
The white portion of the eye acting as a protective outer coating, contains a transparent protective shield called the cornea
Choroid
Middle layer of the eye holding blood vessels, the iris, and the pupil (which controls the amount of light entering the eye.) Also contains the aqueous humor, a watery like fluid that fills the front compartment of the eye
Retina
Located on the back surface of the eyeball, Containing the light sensitive cells (rods and cones), that receive and transmit impressions to the brain through the optic nerve
Ears
Hearing organs That transmit nerve impulses associated with sound waves
Function of the external ear?
A funnel to gather sound waves and pass them through the ear canal to the eardrum
Tympanic membrane
The eardrum, a tightly stretched membrane that separates the outer ear canal from the middle ear
Three small bones in the Middle ear?
malleus, incus, and stapes
Location of the receptors and nerve endings that transmit nerve impulses to the brain
A spiral shaped tube called the cochlea channels these vibrations within the inner ear
Nose
The organ of smell, receptors are located in the mucous membranes of the nasal cavity and are sensitive to chemicals carried through the air.
Tongue
The organ of taste. A combination of four types of taste and 80 types of chemical odors produce specific flavors
Skin
The largest organ, containing many nerve endings at and below the surface. Touch receptors can distinguish textures, hot and cold, pressure and pain.
