#science/y9/nervous-system
Muscle tissue and optic nerve §
- cut away tissue, work around the eyeball and do not cut the optic nerve
- highlight optic nerve (sends image to brain)
Cut eyeball §
- Cut around the tissue until it is similar to the eyeball on the right
Cornea §
- at the front there is the protective layer and where light enters the eye (cornea)
- slightly transclucent
- it is opaque because of preservatives now, but in a living eye it would be transparent
Sclera §
- cornea is continuous with the sclera - maintains the shape of the eye
- protects the inner part of the eye
Better image of optic nerve §
- out the back is again, the optic nerve, except now since the eye is trimmed it is much easier to see
- more than a million fibres in optic nerve, very durable
- behind is optic disc - blind spot of retina - no cones / rods
Slicing the eye equator §
- slice the eye like its paper, making sure not to damage anything underneath
- make sure to keep the bottom of the scissors up against the sclera wall
Retina §
- opaque layer at the back
- retina has the photoreceptors (rods for b&w and cones for colour)
- light turned into electrical signals then transmitted to optic nerve
- not very securely in place - only attached at optic nerve
Vitreous humour gel §
- fills the inner part of the eyeball
- mainly helps the eyeball keep its shape
- light is transparent, so light passes right through it as it is a transparent gel
- pull the vitreous humour out
Choroid §
- richly supplied with blood and supplies nutrients to other parts of the eye
- very dark - prevents light from scattering
- choroid is next layer in
Lens §
- make sure to pull out and place above newspaper and record
- lens focuses light on retina
Ciliary body §
- lens is attached to ciliary body - a muscle that controls shape of lens
- continuous with the choroid
Pupil §
- This opening is the pupil
- It lets light in