Iris is part of
sclerotic
choroid/uvula
choroid and retina
sclerotic and choroid
Cornea transplantation is outstandingly successful because
cornea is easy to preserve
cornea is not linked up with blood vascular and immune systems
the technique involved is very simple
cornea is easily available
In the chemistry of vision in mammals, the photosensitive substance is called
sclerotin
retinal
rhodopsin
melanin
Acute vision is present in
vulture
shark
bat
frog
In which animal nerve cell is present but brain is absent?
Sponge
Earthworm
Cockroach
Hydra
Sensitive pigmented layer of eye is
cornea
retina
iris
Afferent nerve fibres carry impulses from
effector organs to CNS
receptors to CNS
CNS to receptors
CNS to muscles
Function of iris is to
move lens forward and backward
refract light rays
bring about movements of eye lids
alter the size of pupil
Retina is most sensitive at
optic disc
periphery
macula lutea
fovea centralis
Respiratory centre is situated in
cerebellum
medulla oblongata
hypothalamus
cerebrum
