The Sense Organs Flashcards
extensions of the CNS that allow it to monitor what is going on inside and outside the animal via specially modified dendrites
Sensory Organs
specially modified dendrites that, when triggered by an appropriate stimulus, generate nerve impulses which are then interpreted in the CNS as a particular sensation
Sensory Receptors
Sensory receptors of common domestic animals are sensitive to what 4 types stimuli? Give examples
- Mechanical Stimuli - touch, hearing, balance
- Thermal Stimuli - hot, cold
- Electromagnetic Stimuli - vision
- Chemical Stimuli - taste, smell
What are the 2 types of senses and how many are there?
- General Senses - 5
- Special Senses - 5
List the 5 general senses
- Visceral sensations
- Touch
- Temperature
- Pain
- Proprioception
List the 5 special senses
- Taste
- Smell
- Hearing
- Equilibrium
- Vision
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
- Visceral - chemical + mechanical
- Touch - mechanical
- Temperature - thermal
- Pain - mechanical, chemical or thermal
- Proprioception - mechanical
- Taste - chemical
- Smell - chemical
- Hearing - mechanical
- Equilibrium - mechanical
- Vision - electromagnetic
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
General Senses
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
Visceral Sensations
the sensation of something being in contact with the surface of the body
Tactile Sense
There are different types of touch and pressure receptors. Name 4 sensations produced by them
- Light contact
- Deep pressure
- Vibration
- Hair movement
Which nervous system activates mechanisms to correct hyperthermia and hypothermia?
CNS
receptors detect increases or decreases in body temperature and transmit the information to the CNS
Temperature Receptors
How many types of temperature receptors are there and what are they?
- Superficial Temperature Receptors
- Central Temperature Receptors
receptors that increase their generation of nerve impulses when the temperature increases to bring attention to the conscious mind
Heat Receptors
receptors that increase their generation of nerve impulses when the temperature decreases to bring attention to the conscious mind
Cold Receptors
the sense that protects the body from damage by alerting the CNS to potentially harmful stimuli
Pain
the most common and widely distributed sensory receptors that protect the body from damage by potentially harmful stimuli
Nociceptors
Nociceptors are only absent from where?
The brain
the process of experiencing pain
Nociception
What are the 4 steps of nociception?
- Transduction
- Transmission
- Modulation
- Perception
the step in nociception at the sensory nerve ending when the painful stimulus is converted to a nerve impulse
Transduction
the step in nociception when the nerve impulse travels up the sensory nerve fibers to the spinal cord
Transmission
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
Modulation
the step in nociception when the painful impulses are recognized by several areas of the brain
Perception
What are the 2 classifications of pain?
- Location
- Chronicity
List the pain classifications based on location
- Superficial
- Deep
- Visceral
List the pain classifications based on chronicity
- Acute
- Chronic
pain classification that affects the skin and subcutaneous areas
Superficial Pain
pain classification involving muscles and joints
Deep Pain
pain classification relating to the internal organs
Visceral Pain
pain classification described as sharp and intense
Acute Pain
pain classification described as dull and aching
Chronic Pain
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
Proprioception is achieved by a variety of stretch receptors located in what 4 structures?
- Skeletal Muscles
- Tendons
- Ligaments
- Joint Capsules
significantly elevated body temperature
Heatstroke
List 3 early clinical signs of heatstroke
- Weakness
- Confusion
- Very rapid HR + RR
What is the maximum body temperature compatible with life?
10º F over animal’s normal body temperature
What is an early clinical sign of hypothermia?
Extremely slow HR + RR
Why is it important to keep anesthetized and animals recovering from anesthesia warm?
- The cold room and surgical table can cause hypothermia in an anesthetized state.
- Slowed HR + RR indicate slowed metabolic reactions
- Slows the metabolism of the anesthetic agent at the end of a surgery
- Longer to wake up
the ability to perceive sensations
Esthesia
the complete inability to perceive sensation
Anesthesia
What are 2 types of anesthesia used in vet med?
- General
- Local
anesthesia that involves a complete loss of sensory perception accompanied by loss of consciousness
General Anesthesia
How is general anesthesia administered?
- Injection
- Inhalation
General anesthesia suppresses what 3 things?
- CNS
- Cardiovascular function
- Respiratory function
anesthesia that produces a loss of sensation from a specific area of the body without affecting consciousness
Local Anesthesia
How is local anesthesia administered?
Injection into areas where sensory nerve fibers pass
Local anesthesia suppresses what 2 things?
- Transmission of impulses through the site
- Prevents sensory information from reaching the CNS
the decreased perception of pain
Analgesia
a drug that produces a decreased perception of pain and is often used to make animals with severe pain more comfortable
Analgesic Drug
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
How can you prevent wind-up?
- Administering analgesic or local anesthesia before or during surgery
- Small amounts of several drugs with different analgesic/anesthetic mechanisms > better than 1 large dose of a single drug
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
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
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
small, elevated structures on the tongue that house the majority of taste buds
Papillae
List the types of gustatory papillae
- Conical Papillae
- Circumvallate Papillae
the mechanical sense that converts vibrations of air molecules into nerve impulses that are interpreted by the brain as sound
Auditory Sense
the area of the ear that acts as a funnel to collect sound wave vibrations and direct them to the eardrum
External Ear
What are the 3 components of the external ear?
- Pinna
- External Auditory Canal
- Tympanic Membrane
the funnel-like structure composed of auricular cartilage and skin that collects sound wave vibrations and directs them into the external auditory canal
Pinna
a soft, membrane-lined tube that begins at the base of the pinna and carries sound waves to the tympanic membrane
External Auditory Canal
a thin connective tissue membrane that is tightly stretched across the opening between the external auditory canal and the middle ear cavity
Tympanic Membrane
the air-filled cavity of the ear that amplifies and transmits the vibrations from the eardrum to the inner ear
Middle Ear
List the components of the middle ear
- Ossicles
- Eustachian Tube
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
a tiny muscle that assists in the cochlear damage-control process by restricting the movement of the stapes in response to loud sounds
Stapedius
the ossicle attached to the tympanic membrane that forms a synovial joint with the middle ossicle
Malleus