Download - 10.01 Mammalian Eye as a Sensory Organ
10.01 Mammalian Eye as a Sensory Organ
HKAL | Modern College
Session Objectives Structure of Mammalian Eye Functions vs. Structures Accommodation Next Session
Structure of Mammalian Eye
Structure of Mammalian Eye
Functions vs. StructuresStructure
結構Function
功能Eyelid眼瞼
protects the cornea from mechanical and chemical damage and the retina from bright light by reflex action
保護角膜免受機械性或化學性損害，及透過反射動作保護視網膜免受強光損害
Conjunctiva
結膜thin transparent layer of cells protecting the cornea and continuous with the epithelium of eyelids
是透明的細胞薄層，保護角膜，與眼瞼的上皮相連Cornea
角膜transparent front part of the sclera
是結膜的透明前部份the curved surface acts as a main structure refracting (bending) light towards the retina
彎曲的表面作為主要結構以折射 (扭曲 )光線至視網膜protect the front part of the eye
保護眼睛的前部份
Functions vs. StructuresStructure
結構Function
功能Ciliary muscles & Suspensory ligament
睫狀肌及懸靭帶
contraction and relaxation of circular and radial muscles regulate the tension of the suspensory ligament which alters the shape of the lens
環肌及放射肌的收縮及放鬆會調節懸靭帶的張力，從而改變晶體的形狀
Lens
晶體transparent, elastic biconvex structure
是透明及富彈性的雙面凸透鏡結構provides fine adjustment for focusing light on to the retina and separates the aqueous and vitreous humour
提供精確調節以聚焦光線至視網膜，以及分隔水狀液及玻璃狀液
Functions vs. StructuresStructure
結構Function
功能Iris
虹膜circular muscle containing the pigment giving eye its color
是為環肌，載有色素，令眼睛有顏色it separates the aqueous humour region into anterior and posterior chambers
分隔水狀液區域為前後間隔controls the amount of light entering eye
控制進入眼睛的光線量Pupil
瞳孔opening in iris, all light enters eye through this
虹膜的孔，光線經此進入眼睛
Functions vs. StructuresStructure
結構Function
功能Choroid
脈絡膜rich in blood vessels supplying nutrient and oxygen to the retina
有大量血管以供應養份及氧氣予視網膜covered with pigment cells preventing reflection of light within the eye
表面佈滿色素細胞，防止光線於眼睛內作反射Retina
視網膜contains the photoreceptor cells, rods and cones
載有光感受器細胞，視桿細胞及視錐細胞Optic nerve
視神經bundle of nerve fibers carrying impulses from the retina to the brain
神經纖維束，將視網膜的 [神經 ]脈衝傳遞至腦部Blind spot
盲點point where the optic nerve leaves eye
是為視神經離開眼睛的點there are no rods or cones here, therefore it is not light-sensitive
此處無視桿或視錐細胞，所以不對光線敏感Fovea / yellow spot
黃點most sensitive part of retina, contains cones only
是為視網膜上最敏感的部份，只載有視錐細胞most light rays are focused here
大部份光線均聚焦至此點
Functions vs. StructuresStructure
結構Function
功能Aqueous humour
水狀液clear solution of salts
清晰的鹽溶液supply oxygen and nutrients to the conjunctiva, cornea and the lens
供應氧氣及養份至結膜，角膜及晶體Vitreous humour
玻璃狀液clear semi-solid substance
清晰的半固態物質supporting the eyeball
支持眼球
Functions vs. Structures
Functions vs. Structures
Functions vs. Structures
Accommodation It is a reflex mechanism by which light rays
from an object are brought to focus on the retina這是反射機制，可將來自物件的光束聚焦至視網膜上
AccommodationLight from Distant Object
來自遠方物件的光線Light from Near Object
來自附近物件的光線1) circular ciliary muscle relaxed
環睫狀肌鬆弛1) circular ciliary muscle contracted
環睫狀肌收縮2) suspensory ligament tauts (under tension)
懸靭帶蹦緊（張力）
2) suspensory ligament slacks
懸靭帶鬆弛
3) lens pulled out thin (less convex)
晶體拉緊變薄（凸出較少）3) elastic lens restores its shape (more convex)
富彈性的晶體回復形狀（凸出較大）4) light focused on retina
光線聚焦至視網膜4) light focused on retina
光線聚焦至視網膜5) Divergence response
散開反應 Both eyes are directed at the distant object for better vision
兩眼會引導至遠方物件達致較佳視覺
5) Convergence response
聚合反應 Both eyes are directed at the near object for better vision.
兩眼會引導至附近物件達致較佳視覺
Accommodation
Wrap Up
Next Session Pupil Reflex Vision
Day Vision Light Vision Night Blindness Color Blindness
Other Eye Disorders
