Chapter 10 sense Organs

Heatstroke

A dangerous body reaction to prolonged exposure. As the animals for temperature rapidly rises, the animal becomes week and confused and a lapse into unconsciousness.

Cochlear duct

A long, fluid filled tube that runs the length of the cochlea it contains the receptor organ of hearing the organ of corti

Eardrum

Common name for the tympanic membrane. The paper-thin, connective tissue membrane that is tightly stretched across the opening of the external ear canal into the middle.

General anesthesia

Complete loss of sensory perception accompanied by loss of consciousness.

Transmission

Conduction of a nerve impulse along a nerve fiber.

Transduction

Conversion of a sensory stimulus to a nerve impulse.

Pinna

Externally visible part of the ear that collects sound waves and funnels them down into the external ear canal; the ear flap.

Retina

Inner nervous layer of the eye where the photoreceptors are located. The refractive structures of the eye form an image on the retina that is converted to nerve impulses by the photoreceptors (rods and cones)

Sensory receptor

A modified nerve ending that converts mechanical, thermal, chemical, or electromagnetic stimuli into a nerve impulses that travel to the CNS.

Macula

A patch of sensory epithelium in the vestibule of the inner ear.

Ciliary body

A portion of the uvea, or middle vascular layer, of the eyes.

Tapetum

A shortened name for the tapetum lucidum.

Hyperthermia

An abnormally high body temperature.

Hypothermia

An abnormally low body temperature that slows down all metabolic processes.

Ampulla

An enlargement in each semicircular canal that contains the receptor structure ( the crista).

Wind up

An exaggerated pain response that can be produced when the spinal cord is bombarded with severe or chronic pain impulses.

Pain

An unpleasant sensory response caused by the stimulation of pain receptors in the body.

Analgesia

Decreased perception of pain.

Otolith

Ear stone ( tiny crystals) they help the macula keep track of the position of the head.

Tectorial membrane

Gelatinous sheet that lies on the hair cells of the organ of corgi in the cochlea

Taste

Gustatory sense

Tactile sense

Hairs sensitive to touch.

Tapetum lucidum

Highly reflective area of the choroid in the back of the eye of most domestic animals.

Choroid

Located between the sclera and the retina.

Local anesthesia

Loss of sensation from a localized are of the body

Third eyelid

Nictitating membrane

Oval window

Membrane covered opening into the cochlea that the stapes lies against.

Round window

Membrane-covered opening into the cochlea that functions as a pressure relief device.

Tarsal gland

Merino maim glands of the eyelid margins.

Middle ear

Middle portion of the ear, air filled cavity in the temporal bone of the skull.

Visceral sensation

Miscellaneous interior body sensations. They include hunger and thirst and stretching sensations from hollow internal organs.

Ciliary muscle

Multiunit smooth muscles of the ciliary body that adjusts the shape of the eyes land.

Smell

Olfactory sense

Stapes

One of the three ossicles (stirrup)

Incus

One of the three, the tiny bones that transmit sound wave vibrations across the middle ear. The Angus, or Ansell, is the middle of the three ossicles.

Malleus

One of three ossicles (hammer)

Utricle

One of two saclike spaces (the saccule is the other one) in the vestibule of the inner ear that contain sensory structures that monitor the position of the head.

Saccule

One of two saclike spaces (the utricle is the other one) in the vestibule that cont

Lacrimal puncta

Openings in the upper and lower eyelid margin's located near the medial campus of the eye they drain tears away from the surface of the eye.

Nociception

Pain perception

Nociceptor

Pain receptors

Cone

Photoreceptors in the retina of the eye that perceive color and detail.

Rod

Photoreceptors in the retina of the eye that perceive dim light images in shades of gray.

Vestibule of the ear

Portion of the inner ear that senses the position of the head

Organ of corti

Receptor organ of hearing located in the cochlea.

Modulation

Regulating or changing something

Temperature sense

Sense of hot and cold.

Olfactory sense

Sense of smell

Pressure

Sense of something pressing on the body surface; often combined with the tactile sense, which is the sense of touch.

Photoreceptor

Sensory receptors that convert photons of light energy to nerve impulses that are interpreted by the brain as vision; rods and cones.

Ossicle

Skull bones that are the bones of the ears.

Touch

Tactile sense

Special sense

Taste, smell, hearing, equilibrium, and vision. All located in the head.

Canthus

The corner of the eyelids where they come together. Each eye has a medial and lateral canthus

Tympanic membrane

The eardrum.

Optic disc

The area of the retina where nerve fibers on its surface converge to form the beginning of the optic nerve.

Hearing

The auditory sense; the mechanical sense that converts the soundwave vibrations of air molecules to nerve impulses that are interpreted by the brain as sounds.

Fundus of the eye

The caudal interior surface of the eye. It includes the retina and optic desk.

Cornea

The clear window on the front of the eye that admit light to the interior of the part of the outer fibrous layer of the eyeball.

Vitreous compartment

The compartment of the eye behind (caudal to) the lens and ciliary body.

Aqueous compartment

The compartment of the eye in front of(rostral to) the lens and ciliary body.

Perception

The conscious recognition of something; for example, in the process of nociception, pain nerve impulses are perceived in the brain.

Endolymph

The fluid in the receptor structures of the inner ear.

Perilymph

The fluid that surrounds the membranous portion of the inner ear, where the sensory receptors of the inner ear are found.

Accommodation

The focusing of the lens of the eye to allow close up and distant vision.

Cupula

The gelatinous structure that sits on top of the receptor hairs in the crista ampulla rid of the semi circular canals.

Conjunctiva

The thin, transparent membrane that covers the front portion of the eyeball and lines the interior surfaces of the eyelids.

Limbus

The junction of the cornea and sclera of the eye.

Eyelid

The kinds of conjunctiva lined folds of skin that protect and cover the eyeball.

Lacrimal gland

The main tear producing glands. It is located dorsal and lateral to the eyeball inside the bony orbit.

Uvea

The middle, vascular layer of the eye. It includes the choroid, the ciliary body, and the iris.

Inner ear

The most internal portion of the year. It is contained in the temporal bone and contains both hearing and equilibrium structures.

Pupil

The opening in the center of the iris.

External ear

The outer portion of the ear year. It consists of structures that collect and transmit sound waves to the middle ear: that Pinna, the external auditory canal, and the tympanic membrane.

Posterior chamber

The portion of the aqueous compartment of the eye behind(caudal to) the iris.

Anterior chamber

The portion of the aqueous compartment of the eye in front of (rostral to) the iris.

Proprioception

The sense of body position and movement.stretch receptors in skeletal muscles, tendons, ligaments, and joint capsules send impulses to the nervous system.

Gustatory sense

The sense of taste.

Equilibrium

The sense that helps an animal maintain its balance by keeping track of the position and movement of its head.

General sense

The senses that are distributed throughout the body. They are receptors are fairly simple, and they keep the central nervous system informed about general conditions inside and outside the body.

Crista

The short name for the receptor structure of the semicircular Canal's.

Extra ocular eye muscle

The small skeletal muscles that move and position the eyeballs.

Cochlea

The snail shell shaped cavity in the temporal bone of the skull that contains the hearing portion of the inner ear.

Vitreous humor

The soft, gelatinous fluid that fills the vitreous compartment of the eye.

Conjunctival sac

The space between the bulbar ad pal penal portions of the conjunctive; the space between the eyelid and eyeball.

Canal of schlemm

The structure that drains aqueous humor from the anterior chamber of the eye. It is located at the edge of the anterior chamber, where the iris and the cornea meet.

Meibomian gland

The tarsal glands of the eyelid margins. They produce a waxy substance that helps prevent tears from overflowing onto an animals face.

Lacrimal apparatus

The tear producing and draining structures of the eyes.

Bulbar conjunctiva

The transparent membrane that covers the front portion of the eyeball.

Palpebral conjunctiva

The transparent membrane that lines the inner portion of the eyelid.

External auditory canal

The tube that begins at the base of the Pinna and carries soundwaves to the tympanic membrane.

Nasolacrimal duct

The tube that carries tears from the lacrimal sac to the nasal cavity.

Eustachian tube

The tube that connects the middle ear cavity with the pharynx. It allows equalization of the air pressure on the two sides of the tympanic membrane.

Sclera

The white portion of the eye; part of the outer, fibrous layer of the eyeball.

Nictitating membrane

Third eyelid

Semicircular canal

Three semicircular canals in each inner ear that are part of the vestibular system. They sense rotary motion of the head.

Suspensory ligament

Tiny ligaments that attach to he periphery of of the lens of the eye and connect it to the ciliary body.

Aqueous humor

Watery fluid that fills the aqueous compartment of the eye. It is produced in the posterior chamber and drain from the anterior chamber by the canal of Schlemm.