Neural Control & Coordination
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Withdrawal of the hand when it touches a hot object.
Touching lips of a nursing baby evokes sucking reflex.
Closing of the eyelids when light falls on them.
If a child sees or smells a food unknown to him, he does not salivate. But
if he sees or smells that food every time before tasting it, he salivates
(conditioned reflex).
The pathway of impulses in a reflex action is called Reflex arc.
It consists of:
A receptor organ: It receives the stimulus.
Sensory (afferent) neuron: It transmits impulses from sense organ to
CNS.
Intermediate (connector) neuron : It connects sensory and motor
neurons.
Motor (efferent/effector/excitor) neuron: It conducts impulse from the
CNS to effector organ.
An effector organ (muscle/gland): It responds to impulse.
SËÑSË ØRGÅÑS
01
These are the organs that detect the changes in the
environment and convey the information to the CNS.
02
It includes eye, ear, nose, tongue & skin.
ËÝË
Two
eyes
are
located in sockets
of the skull called
orbits.
The adult human
eyeball is nearly a
spherical structure.
Eyeball has three
layers:
Sclera,
Choroid and Retina.
Blind spot
Optic nerve
Fovea
Retina
Vitreous humour
Choroid
Rectus muscle
Sclera
Eyelid
Eyelash
Cornea
Pupil
Iris
Aqueous
chamber
Lens
Conjuctiva
Suspensory
ligament
Ciliary body