Chapter 12 Flashcards
1
Q
Define sensation
A
Conscious or unconscious awareness of external or internal stimuli
2
Q
Define perception
A
Conscious awareness and interpretation of sensations
3
Q
Define sensory receptor
A
Specialized structures at the end of peripheral nerves that respond to stimuli
4
Q
What do Mechanoreceptors respond to?
A
Changes in pressure ( touch, vibrations, stretch)
5
Q
What do Thermoreceptors respond to?
A
Changes in temperature
6
Q
What do Photoreceptors respond to?
A
Changes in light
7
Q
What do Chemoreceptors respond to?
A
Changes in chemical concentrations
8
Q
What do Nociceptors respond to
A
Extreme stimuli producing the sensation of pain
9
Q
Define sensory adaptation
A
- Process by which a sensory receptor becomes less stimulated following continuous stimulation
- Occurs due to either: Decreased response from receptors or cerebral cortex
- E.x.: Loud music become tolerable.
- Exception is nociceptors (Pain by over stimulation of a receptor)
10
Q
What are somatic senses?
A
They are the receptors associated with skin, muscle,joints, and the viscera.
11
Q
What are the three groups of somatic senses?
A
- Exteroceptive Sense: Detects changes at the body’s surface
- Proprioceptive Sense: Detects changes in body’s position
- Visceroceptor Sense: Detect changes in viscera (pain)
12
Q
What are the three main receptors associated with Touch and Pressure?
A
- Free nerve endings
- Meissner’s Corpuscles
- Pacinian Corpuscles
13
Q
Where are free nerve endings found?
A
Located in epithelium and connective tissue
14
Q
What are some characteristics of Meissner’s Corpuscles?
A
- Dendritic endings
- Surrounded by Connective Tissue
- Mechanoreceptors
- Light touch (in lips,palms,soles,fingertips)
15
Q
What are some characteristics of Pacinian Corpuscles?
A
- Dendritic endings
- Surrounded by Connective tissue
- Mechanoreceptors
- Heavy Pressure ( abundant in deep dermal layer)
16
Q
Discuss the two types of temperature receptors
A
Heat Receptors : sensitive to temperatures above 25°C
unresponsive at temperatures above 45°C (will trigger pain)
Cold Receptors : Sensitive to temperatures between
10°C and 20°C (Below 10°C triggers pain)
Both display rapid sensory adaptation
17
Q
What are some characteristics of Nociceptors?
A
- Detect pain
- Serves to protect against further tissue damage
- Can be activated by many different stimuli (temp,pressure, chemoreceptors)
- Generally do not display sensory adaptation
18
Q
What are some characteristics of Visceral Pain?
A
- Visceral receptors produce the sensations
- Commonly stimulated by pressure and/or a decrease in Oxygen
19
Q
What is reffered pain?
A
- Pain that feels as if it is originated from a part other than the site being stimulated
- Due to shared nerve pathway
20
Q
What are characteristics of Acute Pain?
A
- Occurs Rapidly
- Not present in deep tissue
- Sharp,fast, “prickling” pain
- Conducted on myelinated fibers
- Ceases when stimulus is removed
21
Q
What are characteristics of Chronic Pain?
A
- Beings slowly and increases in intensity over time
- Can occur anyway
- Dull, aching, burning pain
- Conducted on unmyelinated fibers
- Can continue after stimulus is removed
22
Q
Define inappropriate pain
A
pain sensations that are not warning about impending tissue damage
23
Q
What are Analgesics?
A
- Help reduce inappropriate pain by blocking formation of prostaglandins such as:
- Acetylsalicylic Acid (Aspirin), Acetaminophen (Tylenol), Ibuprofen (Motrin)
24
Q
What are stretch Receptors?
A
Proprioceptors that send information to spinal cord and brain
concerning the position and tension of a given muscle.
25
What are characteristics of Muscle Spindles? (In reference to Stretch Receptors)
* Located in skeletal muscle
* Stimulated when skeletal muscle relaxes (elongates) and therefore the spindle is stretched
* Produces the “stretch reflex”
* Opposes the lengthening of the muscle and help maintain the desired position of a limb
26
What are characteristics of Golgi Tendon Organs? (In reference to Stretch Receptors)
* Found at tendons
* Connected to skeletal muscle fibers and innervated by a sensory neuron
* High threshold and stimulated by increased tension
* Help maintain posture and prevents tearing of tendon
27
What are the four tastes of the tongue?
1. Sweet- tip of tongue
2. Sour- lateral tongue
3. Salt - perimeter of tongue
4. Bitter -posterior tongue
28
What are the different areas of the ear?
1. External Ear
2. Middle Ear
3. Inner Ear
29
What are the structures of the external ear?
* Auricle: represents the outer ear ; comprised of cartilage
* External auditory meatus : an S shaped tube that leads to the tympanic membrane (canal)
30
What are the structures of the middle ear?
* Tympanic membrane: eardrum
* Tympanic cavity: air filled space behind the eardrum separates the outer/inner ear (within are the auditory ossicles)
31
What are the structures of the inner ear?
* Complex system of interconnected chambers and tubes called labyrinths
* Body labyrinth
* Membranous labyrinth
32
List the three auditory ossicles and give a definition.
* Malleus (hammer): connected to the tympanic membrane
* Incus (anvil): connects the malleus to the stapes
* Stapes (stirrup): connects the incus to the oval window
33
What is the function of the Middle Ear?
1. Transmission of vibrations from the outer ear to the inner ear
2. Amplification of the vibrations
34
What is the Tympanic Reflex?
* A reflex that reduces pressure from loud sounds that could produce damage
* During the reflex, the muscles contract, moving the malleus and stapes; this reduces the ability of the ossicles to transmit vibrations
35
Where does the tensor tympani attach and what happens when contacted?
* Attaches to the malleus and the auditory tube
* When contracted, it pulls the malleus inward
36
Where does the Stapedius attach and what happened when contracted?
* Attaches the stapes and tympanic and tympanic cavity.
* When contacted pull the stapes outward
37
What is the Auditory Tube?
* A passage way which connects the middle ear to the throat.
* Function: to equalize pressure on both sides of the tympanic membrane, which is necessary for proper hearing.
38
What is the oval window?
An opening in the wall of the tympanic cavity which the stapes is attached to.
39
Where are perilymph contain?
Fluid that fills the space between the bony and membranous labyrinths
40
Where are endolymph contain?
Fluid that fills the membranous labyrinth
41
What are the three parts of the Labyrinths?
1. Cochlea: snail shaped ports that functions in hearing
2. Semicircular canals: 3 rings that help provide dynamic equilibrium
3. Vestibule: located between the cochlea and semicircular canals; houses membranous structures that serve both hearing and equilibrium
42
Where is the scala vestibuli located?
Upper compartment which extends from the oval window to the apex.
(filled with perilymph)
43
Where is the scala tympani located?
Lower compartment which extends from the apex to the round window
(filled with perilymph)
44
What is the cochlear duct? (Inner Ear)
A portion of the membranous labyrinth within the cochlea between two bony
compartments.
(Filled with endolymph)
45
What separates the cochlear duct from the scala vestibuli membrane?
Vestibular membrane
46
What separates the cochlear duct from the scala tympani?
Basilar membrane
47
What is the sensory receptor for the ear?
* Hair cells (mechanoreceptors)
* Located on the basilar membrane within the Organ of Corti
* Above the hairs cell is the tectorial membrane, contacts top of the hair cell
48
What are the four rectus and what directions do they rotate the eye in?
1. Superior rectus - rotates the eye up and toward the midline
2. Inferior rectus - rotate the eye down and toward the midline
3. Medial rectus - rotates the eye toward the midline
4. Lateral rectus - rotates the eye away from the midline
49
What are the two oblique of the eye and what direction do they rotate?
* Superior oblique - rotates the eye down and away from the midline
* Inferior oblique - rotates the eye up and away from the midline
50
What is the area and function of the Outer Tunic?
1. Cornea- transparent anterior portion.
2. Function: focus incoming light rays, no blood vessels
3. Sclera - is the white posterior portion that is continuous with the eyeball
4. Function: Provide protection and site of extrinsic muscle attachment
51
What is the area and function of the Middle Tunic?
* Choroid coat - a membrane joined loosely to the sclera (contains many blood vessel to nourish)
* Ciliary Body - extends from the choroid coat and forms a ring around the front of the eye (Ciliary muscles & Ciliary process)
* Function: Provides nourishment
52
What is the area and function of the Inner Tunic?
* Retina and Rods
* Cones - Color and sharpness
* Optic disc - on the retina where the nerve fibers leave the eye and join w/ optic nerve
* Function: Contains the sensory apparatus for impulse generation
53
What is the Iris?
* A thin diaphragm muscle that surround the pupil.
* Located between the cornea and lens, divides the anterior cavity into 2 separate chambers
54
What is the Retina
* Organ of vision and lining of eyeball
* Sensory receptors serves as photoreceptors
* Use Optic Nerve to the visual cortex (occipital lobe)
55
What is the Optic disc?
* Located at inner tunic
* Where retina nerve fibers leave the eye and join optic nerve
* Blind spot (No photoreceptors)
56
Describe Accommodation
* Process by which the lens changes shape to focus on close objects
* The lens, along with the cornea, is used for focusing incoming light rays
* If light rays are entering the eye from a distant objects , the lens is flat
* If entering from close object, ciliary muscle contract, relaxing suspensory ligs
57
What are the accessory organs of vision?
* eyelids: Prove a protective shield for the eye
* Conjunctive: think, mucous membrane that lines inner surfaces of eyelids
58
What are the lacrimal apparatus?
* Lacrimal gland: Responsible for tears
* Lacrimal sac: Between canaliculi and duct
* Nasolacrimal Duct: Carries tears into nasal cavity
* Superior and inferior canaliculi: small ducts that collect tears
59
What are Photoreceptors?
* Cones - color vision ; produces sharp images
* Rods - night vision (colorless) ; outline of images
