(12.1)--12AnimalAnatomy-TheSenseOrgan-1.pdf

Chapter 12 The Sense OrgansThe function of brain and spinal cord is realized by reflex arc.The receptor is an important part of the reflected arc.Sense OrganThe process of the sensation produced is as follows:First,receptors sense various stimuli(energy)from the internal and external environment and convert this energy into a nerve impulse(action potential).Then,it passes through the sensory nerve to the nerve center.Finally,various sensations are produced after processing in the central cerebral cortex.Exteroceptors:Such as skin sensation of touch,pressure and pain,tongue sensation of taste and smell,eyes,ears,etc.ReceptorInteroceptors:The interoceptors are distributed in viscera,heart and blood vessels,such as pressure sensing,osmotic pressure,ion concentration,etc.Proprioceptors:The proprioceptors are located in muscles,tendons,joints and inner ears.They sense body position and can be stimulated by the state of organs and the position of bodies.Exteroceptors:Such as skin sensation of touch,pressure and pain,tongue sensation of taste and smell,eyes,ears,etc.ReceptorInteroceptors:The interoceptors are distributed in viscera,heart and blood vessels,such as sense pressure,osmotic pressure,ion concentration,etc.ReceptorEyeball:The eyeball is consist of the wall of the eyeball,content,blood vessel and nerve.Visual Organ:the Eyeball and Adnexa of EyeAdnexa of eye:The adnexa of eye include the eyelid,conjunctiva,lacrimal apparatus,extraocular muscle and orbital periosteum.ConjunctivaContentWall of eyeballBlood vesselOptic nerveExtraocular muscleEyeballThe right eye of the cattleThe right eye of the catThe left eye of the canineThe left eye of the horseCornea:The cornea accounts for the first 1/5 of the tunica fibrosa,colorless,transparent and has strong regeneration ability.Tunica FibrosaSclera:The sclera accounts for the posterior 4/5 of the tunica fibrosa,and with scleral sinus.The optic nerve passes through the posterior sclera and forming cribriform plate of sclera.Tunica vasculosaRetinaTunica fibrosaCorneoscleral junctionCorneaScleraTapetum:On the back of the blind spot of the tapetum,there is a green metal triangle part(except for pigs).Tunica VasculosaThe tapetum of the cattleThe tapetum of the catReceptorProprioceptors:The proprioceptors are located in muscles,tendons,joints and inner ears.They sense body position and can be stimulated by the state of organs and the position of bodies.The eyeball is located in the orbital socket.EyeballIt is slightly flat spherical in front and back.The posterior optic nerve of the eyeball is connected to the diencephalon.The eyeball includes the wall of eyeball,contents and vascular nerves.EyeballCorneaRetina optic partTunica vasculosaCiliary bodyIris ChoroidRetinaTunica fibrosaScleraEyeballCorneaPars optica retinaeMiddle layer(Tunica vasculosa)Ciliary bodyIris ChoroidInner layer(Retina)Outer layer(Tunica fibrosa)ScleraPars caeca retinaeEyeballContentsAqueous humorLensVitreous bodyWall of eyeballTunica fibrosa:The tunica fibrous is a thick,tough protective membrane consists of dense connective tissue.It is divided into the anterior cornea and the posterior sclera.Tunica FibrosaTunica vasculosaRetinaTunica fibrosaCorneoscleral junctionCorneaScleraTunica FibrosaCorneaScleral sinusScleraTunica VasculosaCiliary musclePupilCiliary bodyIris ChoroidCiliary zonuleCiliary processesLensThe eyeball contains a large number of tunica vasculosa.Tunica VasculosaBlood vessels-Nourishes the outer layer of the retina through blood circulation in the blood vessels.Pigment cells-Pigment cells form a dark environment that helps them to be sensitive to light.There is a round hole in the center of the iris,called the pupil,granula iridis are on the edge.IrisThe iris is circular,with pigment cells and radiating wrinkles called textures.There have sphincter muscle of pupil(accessory suspensory ligament)in the iris.In the thickened part of the vascular membrane,the annulus surrounds the lens,forming a ciliary ring.Ciliary BodyCiliary ringCiliary muscle-outsideCiliary process-insideCiliary bodyPosition:The retina is located in the the innermost layer of the eyeball,divided into the optic part and caeca part.RetinaRetina optic part:The retina optic part is light red and thin,with papilla nervi optici in the back.Papilla nervi optici:The papilla nervi optici is the place that the visual fiber on retina gathers to deliver to visual center.It has no photosensitive cell,therefore appear on visual field for inherent dark area,called physiology blind spot.Macula lutea:The end point of the visual axis of the retina is macular fovea,which is the special area with the most acute sense of sight on the retina,all of which are cone cells.RetinaPars caeca retinae:The pars caeca retinae is located behind the ciliary body and the iris with pigment distribution,and can not feel the presence of light.RetinaMacula luteaLens:The lens is a elastic transparent body,shaped like a double convex lens,located behind the iris and the pupil,but before the vitreous body.ContentsAqueous humor:Aqueous humor is produced by the ciliary process,with nutrient cornea,lens and vitreous body,which plays a role in maintaining intraocular pressure.ContentsEye anterior chamberVitreous body Eye posterior chamberLensVitreous body:The vitreous body is a transparent colloidal body,mainly composed of water,filling the 4/5 cavity behind the eyeball.It has a refractive function and also supports the retina.Visual PathwayThe visual pathway is as follows:Retinal cone and rod cells Retinal bipolar neurons Retinal ganglion cells Optic nerve Optic chiasma Midbrain anterior colliculus Lateral diencephalon geniculate body Cerebral cortex area 17(occipital lobe)Visual PathwayRetinaRetinaMacula luteaVisual PathwayRetinaRetina:The retina is very thin and complex in structure,which is divided into 10 layers.the Photoreceptor Cells of the RetinaCone cells are responsible for light vision and color vision.Rod cells are responsible for dark vision.the Photoreceptor Cells of the RetinaCone cellBipolar cellRetinal ganglion cellPhotoreceptor cellRod cellthe Photoreceptor Cells of the RetinaCone cellBipolar cellRetinal ganglion cellPhotoreceptor cellRod cellthe Photoreceptor Cells of the RetinaContentsCiliary muscleCiliary bodyCorneaCiliary zonuleCiliary processesLensVitreous bodyContents:The contents of the eyeball are transparent,including aqueous humor,lens,and vitreous.Together with the cornea forms the refractive system of the eye.Normal Vision and CataractsNormal Visual Field and Glaucoma Visual FieldNormal Visual Field and Glaucoma Visual FieldAdnexa of EyeThe adnexa of eye include the eyelid,lacrimal apparatus,eyeball muscle and orbital periosteum.The adnexa of eye include the eyelid,lacrimal apparatus,eyeball muscle and orbital periosteum.Adnexa of EyeLacrimal Apparatus and Eyeball MuscleExternal ear:The external ear mainly collects sound waves,including auricle,external acoustic meatus and tympanic membrane.Auditory and Position Sense Organ:EarMiddle ear:The middle ear mainly conducts sound waves,including tympanic cavity,three ossicular auditory,eustachian tube.Internal ear:The internal ear is the location of auditory and positional receptors,including the osseous labyrinth and membranous labyrinth.External EarThe auricle of the catThe auricle of the canineExternal EarExternal acoustic meatusExternal EarThe lateral part of the external acoustic meatus has cartilaginous.Middle EarTympanic cavityEustachian tubeOssicular auditoryMiddle earOssicular auditoryMiddle EarIncusMalleusStapesInternal EarInternal earOsseous labyrinthMembranous labyrinthAuditory and Position Sense Organ:EarInternal EarAuditory PathwayThe auditory pathway is as follows:Tympanic membrane Ossicular auditory and other auditory apparatus Spiral ganglion Auditory nerve Midbrain posterior colliculus Medial geniculate body Cerebral cortex temporal lobe