Function of iris is to
move lens forward and backward
refract light rays
bring about movements of eye lids
alter the size of pupil
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
One function of parasympathetic nervous system is
contraction of hair muscles
stimulation of sweat glands
acceleration of heart beat
constriction of pupil
Acute vision is present in
vulture
shark
bat
frog
Afferent nerve fibres carry impulses from
effector organs to CNS
receptors to CNS
CNS to receptors
CNS to muscles
Light rays entering the eye are controlled by
pupil
iris
cornea
lens
Sensitive pigmented layer of eye is
retina
sclerotic
Which of the following cranial nerves can regulate heart beat?
X
IX
VIII
VII
Ivan Pavlov performed experiments on
simple reflexes
conditional reflexes
cardiac reflexes
origin of life
The sympathetic nerves, in mammals arise from
sacral nerves
cervical nerves
thoraco-lumbar nerves
III,VII,IX and X cranial nerves