Ch 11 & 12

• Sight (eyes)
• Sound & equilibrium (ears)
• Taste (tongue)
• Smell (nose)

• Cutaneous senses
• heat/cold, pain, presssure/touch
• Visceral senses
• nausea, thirst, hunger
• urination/defecation

ESP

• cone shaped cavity (formed by skull)
• houses & protects the eyeball
• padded w/ fatty tissue
• eyeball connected by 6 short muscles
• covered by eyelid
• contain sebaceous glands (secrete sebum)

protective membrane that lines the exposed surface of the eyeball and acts as a protective covering for the exposed eye surface

produces and stores tears

transports tears

• constant cleaning & lubrication
• act as an antiseptic

• 1. Aqueous Humor - water
• 2. Viterous Humor - jellylike fluid

• "Watery" humor
• bathes the iris, pupil and lens
• fills the anterious and posterior chambers of the eye

• clear, jellylike fluid
• occupies the entire eye cavity behind the lens

• sclera
• choroid
• retina

• outermost laer
• tough, fibrous tissue
• protective shield ("whites of the eyes")
• contains the cornea

• transparent to allow light rays to pass into the eye
• curved surface allowing them to bend the incoming light rays

• Middle layer
• Highly vascularized (rich blood supply)
• Pigmented region that provides nourishment to the eye
• Contains the iris and the pupil

colored ring of tissue whose muscles contract or relax to change the size of the pupil in the center of the iris

Round opening in the iris that allows light rays to enter the intenal eye

• Located behind pupil
• Clear, hard disk in the internal eye. The muscles and ligaments of the ciliary body change its shape to focus light rays onthe retina

• 3rd layer of the eyeball
• contains the nerve endings that receive and help interpret the rays of light as images
• delicate membrane that continues posteriorly and joins the optic nerve
• contains light sensing receptors called rods and cones

• Light sensitive cells in the retia.
• Detect black and white and function in daytime and nighttime vision

• Light sensitive cells in the retina that detect colored light.
• three types of cones, each of which responds to either red, green or blue light.

Smooth muscle that alters the lens of the eye to accommodate for near vision

Chemicals in the retinal cells that have light sensitivity

• External ear
• Middle ear or tympanic cavity
• Inner ear

• 1. Pinna/ Auricle leads sound waves into the auditory canal or external auditory meatus
• 2. Contains cerumen (earwax) to lubricate and protect the ear
• 3. At the end of the canal is the eardrum or tympanic membrane

• 1. Contains the 3 smallest bones in the body (ossicles)
• 2. Ossicles amplify the sound waves
• 4. Eustachian tubes
• 4. Oval window begins the inner ear

• Hammer (malleus)
• Anvel (incus)
• Stirrup (stapes)

• Equalize the air pressure on either side of the eardrum
• Connect the nasal cavity and pharynix to the middle ear

• Oval Window
• Bony labyrinth

• 1. Vestibule Chamber (houses the internal ear)
• 2. Cochlea
• 3. Semicircular canals

Structure of the inner ear that is associated with the sense of hearing. It relays information to the brain via the cochlear branch of the vestibulocochlear nerve (cranial nerve VIII)

Pale lymph fluid found in the labyrinth of the inner ear.

Fluid within the labyrinth of the ear.

Last ossicle vibrates and cuases a gentle pumping against the oval window membrane. Cochlear fluid then vibrates small hairlike neurons. Vibration sends a nerve impulse to the temporal lobe of the brain.

Middle ear amplifies the sound through ossicles

Sound waves enter the external canal and vibrate the eardrum

• Papillae contain taste receptors called taste buds. Found on tongue, lips and back of the throat.
• Taste buds send signals to the brain thru 3 distinct cranial nerves.
• Detect 5 tastes: sweet, sour, salty, bitter and umami (savory)

• Closely related to taste (cannot taste food well with head cold)
• Linked to memory

• Located on skin, tipe of tongue and concentrated in the fingertips
• Allows perception of pain, temperature, pressure, traction and "tickled"

responsible for equilibrium

• endo - into
• crine - to secrete

a series of organs and glands in your body that secretes chemical messengers called hormones into the bloodstream

• hypothalamus
• pituitary gland
• pineal gland

• neurotransmitter
• hormones

the control systems work to bring the body back to homeostasis if they become seriously disrupted. ie when hot, body send blood to the surface of the skin to promote sweating, thus reducing the heat

increases the magnatude of a change away from the set point; vicious cycle.

• Nervous system - neural control
• Hormones - hormonal control
• Body fluids (ie blood) - humoral control

• Is a link between the nervous and endocrine systems
• Controls much of the body's physiology, including hunger, thirst, fluid balance, body temperature
• Controls the pituitary gland

• Often called the master gland
• But only acts on orders from the hypothalamus

• An extension of the hypothalamus
• Launches 2 hormones for the hypothalamus
• Antidiuretic hormone (ADH) and oxytocin

Also controlled by the hypothalamus, but is an endocrine gland too

• Secretes thyroxine (T4) and triiodothyronine (T3) under orders from the pituitary gland ("thyroid hormones")
• Also secretes calcitonin (decreases blood calcium by stimulating bone building cells)

• produces thymosin
• helps with the maturation of WBC during childhood to fight infection

• produces melatonin
• thought to regulate sleep

• produces insulin & glucagon
• controls blood glucose levels

• The Adrenal Medulla
• The Adrenal Cortex

produces epinephrine (adrenalin) and norepinephrine

• makes dozens of steroid hormones known as adrencorticosteroids
• releases hormones under the direction of the anterior pituitary

produce parathyroid hormone (PTH) that regulates the level of calcium in the bloodstream

• Anabolic Steroids
• Hashimoto's disease (a form of hypothyroidism)
• Graves' disease (hyperthyroidism)
• Pheochromocytoma (excess epinephrine)
• Addison's disease (insufficient cortisol production)
• Cushing's syndrome (oversecretion of cortisol)