Nervous System: Senses
olfactory glands
"Bowman glands" produce mucous to moisten olfactory epithelium and dissolve odiferous chemicals
tactile corpuseles
"Meissner corpuseles"; large, encapsulated oval receptors. They are formed from highly intertwined dendrites enclosed b modified neurolemmocytes, which are then covered with sense irregular connective tissue.
tactile cells
"Merkel cells"; which are located in the stratum basale of the epidermis
tactile discs
"Merkel's discs"; are flattened nerve endings that extent to specialized tactile cells
vallate papillae
"circumvallate papillae", 10-12 large cylindrical papillae arranged in a V-shape at the rear of the tongue. Each is surrounded by a deep circular trench. Each has about 250 taste buds on the papillae wall facing the trench.
eyelids
"palpebrae"; Consist of voluntary muscle and skin with tarsal plate. Lines with conjunctiva, a mucous membrane.
lacrimal puncta
(tear ducts) tears drain through these from the lacrimal gland. Each eye has 2.
olfaction
-Sense of Smell whereby volatile molecules (Oderants) must be dissolved in the mucus in our nasal cavity to be detecte
Order that tears travel
1. Lacrimal carnucle, 2. Lacrimal puncta, 3. Lacrimal canaliculus, 4. Lacrimal sac, 5. Nasolacrimal duct
nasolacrimal duct
A duct that carries tears from the lacrimal sac to the nasal cavity
lamina propria
A layer of loose connective tissue in mucous membranes just deep to the basement membrane
adaptation
A reduction in sensitivity to a continually applied stimulus
encapsulated tactile receptors
Are either wrapped by connective tissue or covered by glial cells. Tactile receptors include end bulbs, lamellated corpuscles, bulbous corpuscles, and tactile corpuscles.
visceral sensory receptors
Are located in the walls of the viscera; they respond to temperature, chemicals, stretch, and pain.
Through which cranial nerves does gustatory information travel
CNIX, CN VIII
receptors initiate sensory input to the
CNS
ciliary body
Contracts or relaxes to make the suspensory ligaments either taut or slack and the lens either thinner or fatter.
orbital far
Cushions the posterior and lateral sides of the eye, providing support, protection, and facilitating oxygen and nutrient delivery by the blood.
unencapsulated tactile receptors
Dendritic ends of sensory neurons with no protective coat
tarsal plate
Dense, plate-like frame work with in the middle layer of each eyelid that gives the eyelids their firmness and shape. (also called tarsus)
phasic receptors
Detect a new stimulus or a change in a stimulus that has already been applied but over time their sensitivity decreases
lacrimal gland
Has superior or orbital part and an inferior part. Each eye has one; located within the orbit above the lateral end of the eye; almond size; involves tears; secretes tears; lateral and superior to eye; 12 ducts go from the lacrimal gland to the surface of the conjunctive; blinking washes tears over the surface of the eyeball which then collect in the medial canthus area and drain into lacrimal canals
somatic sensory receptors
Housed within the skin for monitoring tactile sensations (e.g. pressure, vibration, and pain) and within joints, muscles, and tendons for dection of stretch and pressure relative to position and movement of the skeleton and skeletal muscles.
umami stimuli
Japanese for "delicious flavor" it is a taste related to amino acids, such as glutamate and aspartate, to produce meaty flavor
olfactory epitherlium
Lines and supports the superior region of the nasal cavity, including both the superior nasal conchae and the inferior surface of the cribruform
proprioceptors
Located in muscles, tendons, joints. They dectect body and limb movements, skeletal muscles contraction and stretch, and changes in join capsule structure.
special senses
Located only within the head and are specialized, complex organs. (gustation, olfaction, vision, hearing, and equilibrium
ciliary muscles
Multiunit smooth muscles of the ciliary body that adjust the shape of the eye's lens.
fungiform papillae
Mushroom-like protuberances often containing taste buds and located on the sides and tip of the tongue. Contains a few taste buds.
end bulbs
Or terminal bulbs, look like tiny bubbles located at the extreme ends of the axon's branches. Each end bulb is like a miniature container that stores chemicals called neurotransmitters, which are used to communicate with neighboring cells
nociceptors
Pain receptors. Nociceptors are found everywhere in the body except for the brain.
tonic receptors
Response continuously to stimuli at a constant rate
eyebrows
Short, course hairs that overlie the supraorbital margins of the skull. Help shade the eyes from sunlight and prevent perspiration trickling down the forehead from reaching the eyes.
free nerve nedings
Terminal branches of dendrites. They are the least complex of the tactile receptors ad reside closest to the surfact of the skin, usually papillary layer of the dermis.
olfactory bulbs
Terminal ends of the tracts located just above the sinus cavity and just below the frontal lobes that receive information from the olfactory receptor cells.
palpebral fissure
The almond shaped opening between the upper and lower eyelids
choroid
The most extensive and posterior region of the vascular tunic. Highly vascular membrane in the eye between the retina and the sclera in the uveal tract. Provides nourishment to the retina. FIlled iwth pigment from melanocytes.
tarsal glands
The_______are embedded in the tarsal plates, and their ducts open at the eyelid edge just posterior to the eyelashes. These modified sebaceous glands produce an oily secretion that lubricates the eyelid and the eye and prevents the eyelids from sticking together.
conjuctiva
This is the thin, transparent membrane that covers the front portion of the eyeball and the interior surfaces of the eyelids. Vascular
True of False: Unlike other sensory information olfactory pathways do not project to the thalamus.
True
conjuctival fornix
Where the lacrimal duct opens into the eye. The junction of the palpebral and ocular conjunctiva.
classification of receptors
Where the receptors originates
Cavities of the eye superficial to most deep
anterior chamber, posterior chamber, posterior cavity
Which of the following are semicircular canals?
anterior, posterior, lateral
gustatory cells
cells that respond to chemicals dissolved in the saliva are epithelial cells; they are surrounded by supporting cells in taste bud. 7-10 day life span
supporting cells
cells that sandwich the olfactory neurons and sustain the receptors
Transducers
change one form of energy into a different form
modality of stimulus
classifies what stimulus perceives: chemoreceptors, thermoreceptors, photoreceptors, mechanoreceptors, baroreceptors, nociceptors, visceral nociceptors; the stimulating agent
olfactory organs
contain olfactory epithelium with olfactory receptors (neurons sensitive to chemicals dissolved in the overlying mucus), supporting cells, and basal (stem) cells. Their surfaces are coated with the secretions of the olfactory glands.
sphincter pupillae muscle
contraction mediated by parasympathetic fibers from the Edinger-Westphal nucleus, CN III, and constricts pupil
The limbus is the junction between the sclera and:
cornea
palpebral conjunctiva
covers the interior of the eyelid
Free nerve endings are terminal branches of:
dendrities
visceral nociceptors
detect internal body damage w/in the viscera due to excessive stretching of smooth muscle, oxygen deprivation of the tissue, or chemicals released from damaged tissue.
interoceptors
detect internal orans
extereceptors
detect stimuli from the external environment
What type of receptors is found in the mucous membranes
exteroceptors
The three principals layers from the wall of the eye:
fibrous tunic (external layer), the vascular tunic (middle layer), and the retina (inner layer)
filiform papillae
filament-shaped, most numerous, no taste buds, typically gives brain info on textures, used for detecting and manipulating food.
basal cells
functioning as neural stem cells to continually replace olfactory receptor cells
bulbous corpuscles
heavy continuous touch or pressure: joint movements
lacrimal caruncle
houses ciliary glands
Once olfactory receptors are stimulated, which of the different regions of the brain are stimulated?
hypothalamus, cerebral cortex, amygdala
receptive field
is the entire area through which the sensitive ends of the receptor cell are distributed
What type of receptors detect deep pressure and vibration?
lamellated corpuscles
foliate papillae
leaf-shaped; In folds on side of tongue; Contain most sensitve taste buds; Decrease in number with age
olfactory hairs
long cilia that protrude from the nasal epithelium and are continuously bathed by a layer of mucus secreted by underlying glands
medial palpebral
muscle fibers attach on the medial side of the orbit to this area, which in turn is attached to the frontal process of the maxilla,
olfactory receptors
nerve endings that act as the receptors for the sense of smell
Gustatory cells within the taste buds are a specialized type of epithelial cell called _____ cells.
neuroepithelial
referred pain
occurs when sensory nerve signals from certain viscera are precieved as originating not from the organ, but in dermatomes of the skin.
root hair plexus
of sensory nerves surrounds the base of each hair follicle and detects the movement of the shaft.
olfactory basal cells replace:
olfactory cells
papillae
on the dorsal surface of the tongue are epithelial and connective tissue elevations
olfactory hairs house receptor proteins for detecting ______ specific odorant molecule(e).
one
Which of the following structures contain exteroceptors?
oral cavity, skin
ocular conjunctiva
outer surface of eye
general senses
receptors are distributed through the bod and are located in the skin and internal organs
somatic nociceptors
receptors that respond primarily to chemical signals for pain, often released from damaged cells
Eye structures from superficial to deep
sclera. choroid, pigmented layer or retina, neural layer of retina
Somatic receptors
sensory receptors in the skin, muscle, and tendons; body wall
receptors for general senses are usually _____.
simple in structure
localization and sensitivity are easily determined in a _____ field
small
odorant-binding proteins
solubilize the odorants and assist them to receptors. OBP bind to odorants via receptors and then scavange the odrant to prevent further activation. 2 states: One for binding odorants and receptor interaction, second for scavenging
tactile receptors
specialized for the type of sensory stimulation received such as touch, pain and temperature.
lacrimal sac
structure that collects tears before emptying into the nasolacrimal duct
lacrimal canaliculus
structure that drains tears from the lacrimal puncta
sour
tastes are produced by metal acids in the ingested material such as hydrogen ions (H+) in vinegar
sweet
tastes are produced by organic compounds such as sugar other molecules
bitter
tastes are produced primarily by alkaloids suchs as quinine, unsweetened choclate, nicotine, and caffine
salt
tates are produced by metal ions such as sodium (Na+) and potassium (K+)
lateral palpebral
the horizontal line that is form from the interlaced ends of fiber bundles from the upper and lower lids at the lateral palpebral ligament.
taste pore
the opening of the taste bud
gustation
the sense of taste
Which of the following are true of the olfactory hairs?
they are immobile, they are unmyelinated
Sensory neurons housed within the vestibular ganglia monitor changes in the activities of hair cells within the ________ and the _________ _________.
vestibule; semicircular canal
Trachoma
A serious eye infection, and probably the greatest single cause of blindness by an infectious disease; Caused by certain serotypes of Chlamydia trachomatis but not the same ones that cause genital infections.
lacrimal apparatus
A structure of the eye that produce tears and the ducts that drain excess fluid from the front of the eyes into the nose. Including:tear film, lacrimal gland, upper and lower punctum, upper and lower canaliculus, lacrimal sac, and nasolacrimal duct
lamellated corpuseles
"Pacinian corpuscles" composed of several dendritic endings ensheathed with an inner core of neurolemmocytes and out concentric layers of connective tissue.
levator palpebrae superioris
Narrow, tendinous muscles located deep in the eye sockets at the small wings of the sphenoid bone. They end in a wide aponeurosis. They raise the upper eyelid. The levator palpebrae superioris creates the following wrinkles: superior palpebral sulcus and linear sulci, short palpebration furrows, which fan from opposite corners of the eyelids toward each other.