General and special senses, anatomy and physiology of the eye and ear, and the endocrine system
Examples of General Senses:
Examples of Special Senses:
each sensory neuron moniters a specific region called _____; the location of this stimulus is relayed to a certain area of the sensory cortex, this neural connection is call a ______
Pattern of action potentials to relay nerve impulses and provide CNS with such info as intensity, duration, variation, and movement of the stimulus is known as ____
Give an example of the cerebral cortex's inability to distinguish between true and false sensations
Eye rubbing and seeing light.
When the body projects a sensation to another part of the body this is known as ______
describe and give an example of: Tonic receptors
always active; pain receptors
describe and give an example: Phasic receptors
usually innactive unless stimulated; tactile receptors and other receptors for touch
Definition/types of gen. receptor and what it does: Proprioceptors
Receptors for body position
-M. spindle receptors- tell brain about m. position
-Golgi tendon organs- tell brain about tendon position
Definition/types of gen. receptor and what it does: Thermoreceptors
sensors for changes in temp
Definition/types of gen. receptor and what it does: Baroreceptors
Pressure receptors regarding liquid and gas
lamellated corpuscles aka pacinian corpuscles
Definition/types of gen. receptor and what it does: Chemoreceptors
sensors for chemical changes within the body
Definition/types of gen. receptor and what it does: Mechanoreceptors
Tactile corpuscles aka meissner's corpuscles
Tactile or Merkel's disks
Definition/types of gen. receptor and what it does: Nociceptors
Describe the two point discrimination test
way to measure the density of the receptor poulation in a certain region by gradually increasing the distance between points of a compass
Elaborate on receptor adaptation
the reduction in sensitivity to repeated stimulus.
peripheral- decline in response to stimuli at receptors
central- occurs in CNS
Elaborate on olfactory receptors and olfactory glands:
Olfactory receptors are located on epithelium of the nasal cavity. The olfactory glands are located deep to the receptors. More mucus in the nasal cavity means more difficulty of scent reaching the glands.
Three types of taste buds: location and what stimulates them
-circumvallate papillae- located at the rear of the tongue, sensitive to bitter
-fungiform papillae- located in the middle of the tongue, sensitive to salty, sweet and sour
filaform papillae- tip of the tongue, sensitive to texture. no taste buds
Describe a sty:
when a ciliary gland is blocked and becomes inflamed
inflammation of the conjunctiva caused by bacteria, dust, smoke, or air pollutants
flow of tears:
lacrimal ducts-medially across eyeball surface-lacrimal puncta-lacrimal canals-lacrimal sac-nasolacrimal duct drains into the nasal cavity.
3 internal divisions of the eye:
muscles that open and close the eyelids:
levator palpebrae superiorus raises the eyelid
orbicularis oculi muscle closes it
intraocular pressure of the eye is elevated and damages the optic nerve due to blockage of the cleral venous sinus resulting in blindness
Constrictor and dilator muscles of the iris:
Constrictor m.- when contracted means light intensity increased, shrink pupil
dilator m.- when contracted less light, enlarge pupil
1. lacrimal gland ducts
2. superior rectus m.
3. tendon of superior oblique m.
4. lacrmial punctum
5. lacrimal carnucle
6. superior lacrimal canaliculus
7. meial canthus
8. inferior lacrimal canaliculus
9. lacrimal sac
10. nasolacrimal duct
11. inferior oblique m.
12. inferior rectus m.
13. lower eyelid
14. lateral canthus
15. lacrimal gland
1. levator palpebrae superiois
2. superior oblique m.
3. superior rectus m.
4. lateral rectus
5. inferior rectus m.
6. inferior oblique m.
8. medial rectus
rods and cones
Rods vs cones:
rods- sensitive to low light and motion
cones- sensitive to bright light and color
Describe the fovea:
the area of sharpest vision, containing large density of cones
Explain the blind spot:
-optic disk; area of the retina lacking photoreceptors
Explain visual acuity:
aka sharpness of vision. tested with the snellen eye chart
emmetropic; visual acuity of 20/20
myopic; can see close but not far. eye focuses image in front of the retina
hyperopic; can see distant but not close up. focuses an image behind the retina
reduction of sharpness of vision due to an irregularly shaped cornea or lens
causes a form of farsightedness; when the lens loses its elasticity
How vibrations move inward:
vibrates perilymph at round window
pressure waves distort basilar membrane
cause hair cells to vibrate against tectorial membrane
info of region and intensity sent to CNS
what is otitis media?
immflamation of the middle ear
Function of the auditory tube:
equalizes pressure between the external air and the cavity of the middle ear
Function of the semicircular canals:
sense movement (acceleration and decceleration)
sensory receptor for hearing:
this is a slide of the cochlea
-organ of corti
two functions of the inner ear:
balance and hearing
aka motion sickness; when CNS recieves conflicting info
receptor for dynamic equilibrium and what it responds to:
crista in each semicircular duct; responds to head tilting
receptor for static equilibrium and what it responds to:
maculae; sense changes in body position relative to gravity
aka pitch; number of compressed regions that pass a given point in one second
unit to measure the frequency of the waves
aka intensity of a frequency
the height of a sound wave
damage to tympanic membrane or ossicles
damage to the cochlea or cochlear nerve from exposure to loud noise.
Role of endorcrine glands:
in response to stimuli, they produce hormones
regulatory molecules that slowly change metabolic activities
any cell that contain membrane repetors for specific hormones
a stiumus causes a response that either reduces or removes the stimulus. ex- ac unit in a house. or insulin
What does it produce; hypothalamus-
ADH and oxytocin
What does it produce; pituitary gland-
-Anterior lobe- ACTH, TSH, GH, FSH
-Posterior lobe- oxytocin and ADH
What does it produce; pineal gland-
What does it produce; parathyroid gland-
What does it produce; pancreatic islets-
thyroid gland produces too much T4 and T3; increase metabolic rate
Parathyroid glands mostly comprised of:
Three layers of Adrenal cortex:
Zona glomerulosa- outermost
Zona reticularis- deepest
function of glucagon:
raises blood sugar concentration
function of insulin:
lowers blood sugar
what cells compose most of the pancreas?
name the four types of endocrine cells housed by the islets of langerhans
Type I vs Type II diabetes:
Type I- beta cells don't produce enough insulin
Type II- cells are not receptive to the insulin
what do follicular cells of the thyroid produce?
T3 and T4
what do C cells of the thyroid produce?
why is the pancreas known as a "double gland"?
it performs both exocrine and endocrine functions. secretes digestive enzymes and produce hormones that regulate blood sugar metabolism.