The Sense Organs Flashcards
(173 cards)
1
Q
extensions of the CNS that allow it to monitor what is going on inside and outside the animal via specially modified dendrites
A
Sensory Organs
2
Q
specially modified dendrites that, when triggered by an appropriate stimulus, generate nerve impulses which are then interpreted in the CNS as a particular sensation
A
Sensory Receptors
3
Q
Sensory receptors of common domestic animals are sensitive to what 4 types stimuli? Give examples
A
- Mechanical Stimuli - touch, hearing, balance
- Thermal Stimuli - hot, cold
- Electromagnetic Stimuli - vision
- Chemical Stimuli - taste, smell
4
Q
What are the 2 types of senses and how many are there?
A
- General Senses - 5
- Special Senses - 5
5
Q
List the 5 general senses
A
- Visceral sensations
- Touch
- Temperature
- Pain
- Proprioception
6
Q
List the 5 special senses
A
- Taste
- Smell
- Hearing
- Equilibrium
- Vision
7
Q
Match the sense with the type of stimulus:
Sense:
Visceral, Touch, Temperature, Pain, Proprioception, Taste, Smell, Hearing, Equilibrium, and Vision
Type of Stimulus:
Chemical, Mechanical, Thermal, and Electromagnetic
A
- Visceral - chemical + mechanical
- Touch - mechanical
- Temperature - thermal
- Pain - mechanical, chemical or thermal
- Proprioception - mechanical
- Taste - chemical
- Smell - chemical
- Hearing - mechanical
- Equilibrium - mechanical
- Vision - electromagnetic
8
Q
widespread senses whose receptors are fairly simple structures and transmit sensory information to the CNS through peripheral and autonomic nerve fibers to keep the CNS informed about the overall conditions inside and outside the body
A
General Senses
9
Q
sensations that initiate actions designed to secure the needed substances and restore nutrient and fluid homeostasis in the body or to let the body know when an organ is stretching and shouldn’t be
A
Visceral Sensations
10
Q
the sensation of something being in contact with the surface of the body
A
Tactile Sense
11
Q
There are different types of touch and pressure receptors. Name 4 sensations produced by them
A
- Light contact
- Deep pressure
- Vibration
- Hair movement
12
Q
Which nervous system activates mechanisms to correct hyperthermia and hypothermia?
A
CNS
13
Q
receptors detect increases or decreases in body temperature and transmit the information to the CNS
A
Temperature Receptors
14
Q
How many types of temperature receptors are there and what are they?
A
- Superficial Temperature Receptors
- Central Temperature Receptors
15
Q
receptors that increase their generation of nerve impulses when the temperature increases to bring attention to the conscious mind
A
Heat Receptors
16
Q
receptors that increase their generation of nerve impulses when the temperature decreases to bring attention to the conscious mind
A
Cold Receptors
17
Q
the sense that protects the body from damage by alerting the CNS to potentially harmful stimuli
A
Pain
18
Q
the most common and widely distributed sensory receptors that protect the body from damage by potentially harmful stimuli
A
Nociceptors
19
Q
Nociceptors are only absent from where?
A
The brain
20
Q
the process of experiencing pain
A
Nociception
21
Q
What are the 4 steps of nociception?
A
- Transduction
- Transmission
- Modulation
- Perception
22
Q
the step in nociception at the sensory nerve ending when the painful stimulus is converted to a nerve impulse
A
Transduction
23
Q
the step in nociception when the nerve impulse travels up the sensory nerve fibers to the spinal cord
A
Transmission
24
Q
the step in nociception when nerve impulses are either amplified or suppressed through synapses between neurons in the dorsal horns of the spinal cord before traveling to the brain
A
Modulation
25
the step in nociception when the painful impulses are recognized by several areas of the brain
Perception
26
What are the 2 classifications of pain?
1. Location
2. Chronicity
27
List the pain classifications based on location
1. Superficial
2. Deep
3. Visceral
28
List the pain classifications based on chronicity
1. Acute
2. Chronic
29
pain classification that affects the skin and subcutaneous areas
Superficial Pain
30
pain classification involving muscles and joints
Deep Pain
31
pain classification relating to the internal organs
Visceral Pain
32
pain classification described as sharp and intense
Acute Pain
33
pain classification described as dull and aching
Chronic Pain
34
the sense subconsciously keeps the CNS informed about the movements of limbs, the positions of joints, the state of muscle contraction, and the amount of tension being exerted on tendons and ligaments
Proprioception
35
Proprioception is achieved by a variety of stretch receptors located in what 4 structures?
1. Skeletal Muscles
2. Tendons
3. Ligaments
4. Joint Capsules
36
significantly elevated body temperature
Heatstroke
37
List 3 early clinical signs of heatstroke
1. Weakness
2. Confusion
3. Very rapid HR + RR
38
What is the maximum body temperature compatible with life?
10º F over animal's normal body temperature
39
What is an early clinical sign of hypothermia?
Extremely slow HR + RR
40
Why is it important to keep anesthetized and animals recovering from anesthesia warm?
1. The cold room and surgical table can cause hypothermia in an anesthetized state.
2. Slowed HR + RR indicate slowed metabolic reactions
3. Slows the metabolism of the anesthetic agent at the end of a surgery
4. Longer to wake up
41
the ability to perceive sensations
Esthesia
42
the complete inability to perceive sensation
Anesthesia
43
What are 2 types of anesthesia used in vet med?
1. General
2. Local
44
anesthesia that involves a complete loss of sensory perception accompanied by loss of consciousness
General Anesthesia
45
How is general anesthesia administered?
1. Injection
2. Inhalation
46
General anesthesia suppresses what 3 things?
1. CNS
2. Cardiovascular function
3. Respiratory function
47
anesthesia that produces a loss of sensation from a specific area of the body without affecting consciousness
Local Anesthesia
48
How is local anesthesia administered?
Injection into areas where sensory nerve fibers pass
49
Local anesthesia suppresses what 2 things?
1. Transmission of impulses through the site
2. Prevents sensory information from reaching the CNS
50
the decreased perception of pain
Analgesia
51
a drug that produces a decreased perception of pain and is often used to make animals with severe pain more comfortable
Analgesic Drug
52
the exaggerated pain response in a postsurgical patient caused by the amplification of pain signals sent to the brain once they wake up from general anesthesia
Wind-Up
53
How can you prevent wind-up?
1. Administering analgesic or local anesthesia before or during surgery
2. Small amounts of several drugs with different analgesic/anesthetic mechanisms > better than 1 large dose of a single drug
54
senses organized into specific, complex sensory organs and structures all located within the head that are often involved in clinical illnesses and injuries
Special Senses
55
the gustatory sense receptors that detect chemical substances dissolved in the saliva and generate nerve impulses sent to and interpreted as tastes by the brain
Taste Buds
56
tiny openings on the surface of each taste bud that allow dissolved substances to enter the taste buds and contact the sensory receptors
Taste Pores
57
small, elevated structures on the tongue that house the majority of taste buds
Papillae
58
List the types of gustatory papillae
1. Conical Papillae
2. Circumvallate Papillae
59
the mechanical sense that converts vibrations of air molecules into nerve impulses that are interpreted by the brain as sound
Auditory Sense
60
the area of the ear that acts as a funnel to collect sound wave vibrations and direct them to the eardrum
External Ear
61
What are the 3 components of the external ear?
1. Pinna
2. External Auditory Canal
3. Tympanic Membrane
62
the funnel-like structure composed of auricular cartilage and skin that collects sound wave vibrations and directs them into the external auditory canal
Pinna
63
a soft, membrane-lined tube that begins at the base of the pinna and carries sound waves to the tympanic membrane
External Auditory Canal
64
a thin connective tissue membrane that is tightly stretched across the opening between the external auditory canal and the middle ear cavity
Tympanic Membrane
65
the air-filled cavity of the ear that amplifies and transmits the vibrations from the eardrum to the inner ear
Middle Ear
66
List the components of the middle ear
1. Ossicles
2. Eustachian Tube
67
a tiny muscle attached to the malleus that adjusts the tension of the tympanic membrane to help deaden the transmission of extremely loud sound vibrations to the cochlea
Tensor Tympani
68
a tiny muscle that assists in the cochlear damage-control process by restricting the movement of the stapes in response to loud sounds
Stapedius
69
the ossicle attached to the tympanic membrane that forms a synovial joint with the middle ossicle
Malleus
70
the middle ossicle
Incus
71
the ossicle attached to the membrane of the cochlear oval window and forms a joint with the middle ossicle
Stapes
72
the connection between the middle ear cavity and the pharynx that equalizes the air pressure on the 2 sides of the tympanic membrane
Eustachian Tube
73
the area of the ear that contains the sensory receptors that convert the mechanical vibrations to nerve impulses and contain receptors contributing to equilibrium
Inner Ear
74
the spiral cavity of the inner ear that contains structures to convert mechanical vibrations to nerve impulses
Cochlea
75
List the components of the cochlea
1. Organ of Corti
2. Cochlear Duct
3. U-Shaped Tube
4. Basilar Membrane
76
the long tube containing endolymph and houses the organ of Corti
Cochlear Duct
77
the fluid of the inner ear canal that indicate information about sound, position, and balance to the CNS when is it displaced
Endolymph
78
structure located on either side of the cochlear duct that contains perilymph
U-Shaped Tube
79
fluid of the inner ear canal that regulate electrochemical impulses of hair cells necessary for hearing
Perilymph
80
the membrane-covered opening of the U-shaped tube in the cochlea that is attached to the stapes
Oval Window
81
the membrane-covered opening of the U-shaped tube in the cochlea that does not have anything against it
Cochlear (Round) Window
82
a shelf-like structure on which the cochlear duct and organ of Corti run along like a ribbon
Basilar Membrane
83
the gelatin-like membrane that lies gently on top of the hair cells of the organ of Corti and cause the generation of nerve impulses as the hairs bend
Tectorial Membrane
84
the mechanical sense that helps the animal maintain its balance by working with the eyes and proprioceptors to keep track of the positions and movements of the head
Equilibrium
85
List the 2 types of equilibrium receptors
1. Vestibule
2. Semicircular Canals
86
the equilibrium receptor that gives the brain information about the linear motion of the head as well as the position of the head
Vestibule
87
the 2 saclike spaces in the vestibule of the inner ear that are continuous with the cochlear duct, filled with endolymph, and surrounded by perilymph
Utricle and Saccule
88
a patch of sensory epithelium in the utricle and saccule of the vestibule covered by otoliths that consists of hair cells and supporting cells
Macula
89
tiny crystals of calcium carbonate found in the matrix surrounding the macula
Otolith
90
the equilibrium receptors oriented in different planes and at right angles to the each other that give the brain information about the head's rotary motion
Semicircular Canals
91
an enlargement near the utricle end of the semicircular canal that contains the crista
Ampulla
92
the receptor structure in the ampulla that consists of hair cells and supporting cells surrounded by cupula
Crista
93
the gelatinous matrix surrounding the crista that functions as a float to move with the endolymph in the membranous canal and contains no otoliths
Cupula
94
Give the major layers of the eyeball
1. Fibrous Layer
2. Vascular Layer (Uvea)
3. Nervous Layer (Retina)
95
List the components of the fibrous layer of the eyeball
1. Cornea
2. Sclera
96
the avascular layer of the eye that admits light to its interior and gives strength and shape to the eyeball
Fibrous Layer
97
the highly-innervated, transparent "window" that admits light to the interior of the eye
Cornea
98
the abnormal overaccumulation of water in the cornea
Corneal Edema
99
the abnormal deficiency of water in the cornea that causes a cloudy and opaque appearance
Corneal Dehydration
100
makes up the majority of the outer fibrous layer of the eye
Sclera
101
the junction of the cornea and the sclera that can be used as a landmark to describe the position of lesions on the cornea or sclera
Limbus
102
the vascular layer of the eye
Uvea
103
List the components of the uvea
1. Choroid
2. Iris
3. Ciliary Body
104
the structure sandwiched between the sclera and the retina that consists mainly of pigment and blood vessels that supply blood to the retina
Choroid
105
the highly reflective area of the rear of the eye formed by the choroid that acts as a light amplifier to aid low-light vision
Tapetum Lucidum
106
How does the tapetum lucidum amplify light to aid in low-light vision?
1. Light passes through the photoreceptors
2. Light reflects off the tapetum
3. Light passes back through the photoreceptors again
4. Stimulates the receptors a 2nd time
5. Light is amplified
107
What 2 species do not have a tapetum?
1. Swine
2. Humans
108
the muscular diaphragm that controls the amount of light that enters the posterior part of the eyeball
Iris
109
the opening in the center of the iris that dilates in low-light conditions and constricts in bright light
Pupil
110
What are the 2 types of muscle fibers in the iris?
1. Radially arranged fibers
2. Circularly arranged fibers
111
smooth muscle fibers in the iris that dilate the pupil when they contract
Radially arranged fibers
112
smooth muscle fibers in the iris that constrict the pupil when they contract
Circularly arranged fibers
113
the ring shaped structure located immediately behind the iris that contains tiny muscles that adjust the shape of the lens to allow near and far vision
Ciliary Body
114
What are the components of the ciliary body?
1. Ciliary Muscles
2. Suspensory Ligaments
115
the muscle fibers that flatten the lens when relaxed and allow the lens to assume its natural, more rounded shape when they contract
Ciliary Muscles
116
tiny connective structures that attach the ciliary muscles to the periphery of the lens
Suspensory Ligaments
117
the innervated layer that lines the back of the eye and contains the sensory receptors for vision
Retina
118
the caudal interior surface of the eye
Fundus
119
Give the components of the fundus
1. Retina
2. Optic Disc
120
List the major compartments of the eyeball
1. Aqueous Compartment
2. Vitreous Comparment
121
the fluid-filled compartment in front of the lens and ciliary body that contains its associated humor
Aqueous Compartment
122
old anatomical term for fluid
Humor
123
clear, watery fluid located in front of the lens and ciliary body
Aqueous Humor
124
the space of the aqueous compartment located in front of the iris
Anterior Chamber
125
the space of the aqueous compartment located behind the iris and in front of the lens
Posterior Chamber
126
the ringlike exit duct that slowly drains the aqueous humor from the anterior chamber and returns the fluid to the bloodstream
Canal of Schlemm
127
the fluid-filled compartment behind the lens and ciliary body that contains its associated humor
Vitreous Compartment
128
clear, gelatinous fluid located behind the lens and ciliary body
Vitreous Humor
129
the structure of the eye that helps focus a clear image on the retina regardless of whether the object being viewed is close up or far away
Lens
130
the process of changing the shape of the lens to allow close-up and distant vision by the lens and ciliary body
Accommodation
131
the structure in the eye where the visual image is formed, sensed, and converted to nerve impulses that are decoded in the brain to re-form the image in the conscious mind
Retina
132
List the 5 layers of the retina
1. Pigment Layer
2. Photoreceptor Layer
3. Bipolar Cell Layer
4. Ganglion Cell Layer
5. Nerve Fiber Layer
133
the deepest layer of neurons in the retina where you can find rod and cones
Photoreceptor Layer
134
the point of entry of the optic nerve that lacks visual receptors and therefore creates a blind spot on the retina
Optic Disc
135
neurons whose dendrites have been modified into sensory receptors for light
Photoreceptor Cells
136
the main photoreceptors for low-light vision
Rods
137
the light-absorbing pigment found in rod cells
Rhodopsin
138
the main photoreceptors for color and detail
Cones
139
the color sensitive pigment found in cones
Iodopsin
140
a small depression in the center of the retina of humans and primates containing a dense accumulation of cones that has the clearest vision
Fovea centralis
141
the bending of light rays that occurs as the rays pass into a medium of a different optical density, which affects the speed of light transmission
Refraction
142
Does the majority of the refractive work in the eye
Cornea
143
List the 3 components that fine tune images formed by the cornea
1. Aqueous Humor
2. Vitreous Humor
3. Lens
144
a thin, transparent membrane that covers the front portion of the eyeball and lines the interior surfaces of the eyelids
Conjunctiva
145
the thin, transparent membrane that covers the front portion of the eyeball
Bulbar Conjunctiva
146
the thin, transparent membrane that lines the inner portion of the eyelids
Palpebral Conjunctiva
147
the space between the bulbar and palpebral portions of the conjunctiva
Conjunctival Sac
148
the upper and lower folds of skin surrounding the eye that are lined by the conjunctiva
Eyelid
149
the corners where the eyelid come together
Lateral and Medial Canthi (sg. canthus)
150
tiny openings along the margin of each eyelid that produce a waxy substance to prevent tears from overflowing onto the face
Tarsal (Meibomian) Glands
151
a third eyelid located medially between the eyelids and the eyeball of domestic animals and consists of a T-shaped plate of cartilage covered by conjunctiva
Nictitating Membrane
152
includes the structures that produce and secrete tears and the structures that drain them away from the surface of the eye
Lacrimal Apparatus
153
the structures that produce tears and are located dorsal and lateral to each eye inside the bony orbits
Lacrimal Glands
154
List the 3 liquid film layers on the surface of the eye
1. Mucous Layer
2. Tear Layer
3. Oily Layer
155
inner layer of film on the eye that contains antibacterial substances that help protect the eye from infection
Mucous Layer
156
the middle layer of film on the eye that keeps the cornea moist
Tear Layer
157
the outer layer of film on the eye that helps reduce evaporation of the underlying tear layer and prevents tears from flowing over the lid margin
Oily Layer
158
2 small openings near the medial canthi on the upper and lower eyelid margins that drain tears away from the surface of each eye
Lacrimal Puncta (sg. punctum)
159
small skeletal muscles attached to the sclera that hold the eyeballs in place and delicately and accurately move them
Extraocular Eye Muscles
160
What are the 2 main types of extraocular eye muscles in animals?
1. Reticular (straight)
2. Oblique
161
List the 7 extraocular eye muscles in animals
1. Dorsal Rectus
2. Ventral Rectus
3. Medial Rectus
4. Lateral Rectus
5. Dorsal Oblique
6. Ventral Oblique
7. Retractor Bulbi Muscle
162
the abnormal accumulation of free blood between the cartilage and skin of the pinna
Ear Hematoma
163
the permanent scar tissue formed by untreated ear hematomas
Cauliflower Ear
164
List 3 treatment steps for ear hematomas
1. Surgical draining
2. Sutures through the pinna > hold the skin tight against the cartilage > prevents fluid from reaccumulating
3. Treat cause of head shaking > prevent recurrence
165
inflammation of the skin of the external ear canal
Otitis Externa
166
a group of diseases characterized by increased intraocular pressure that causes pain and can lead to blindness
Glaucoma
167
an instrument used to test for glaucoma by measuring the intraocular pressure
Tonometer
168
What causes glaucoma?
Insufficient drainage of aqueous humor
169
an abnormal condition of the eye whereby the lens becomes opaque which impairs vision, particularly in dim light, and can lead to total blindness
Cataract
170
the inflammation of the thin, transparent membrane that covers the front portion of the eyeball and lines the interior surfaces of the eyelids
Conjunctivitis
171
watery
serous
172
bloody
sanguineous
173
pus-like
purulent
