the nervous system is first divided into the cns and the peripheral nervous system.
this consists of the crainial nerves.
brain parts:
cerebral hemisphere- 2 which make up the cerebrum, the largest part. connected by nerve fibres called the corpus callosum.
receives impulses from sensory receptors e.g. heat, cold, touch , sight, taste, smell
controls skeletal movements for voluntary movement
consciousness, memory, language, speech, emotions.
Hypothalamus-synthesis of hormone, osmoregulation and maintains body temperature.
Midbrain- conducts impulses between the hindbrain and forebrain, linked with visual and auditory reflexes.
cerebellum- acts with the cerebrum to produce skilled co ordinated movements, co ordinates balance and posture.
Pons-mainly nerve fibers joining the parts of the cerebrum, control of breathing.
Medulla Oblongata-controls rate and force of heartbeat, coughing, sneezing vomiting etc
The brain develops in the embryo from a neural plate.
fold arise and form a neural tube
3 main sections: forebrain contains: cerebrum and hypothalamus
midbrain contains: midbrain
Hindbrain contains: pons, cerebellum and medulla oblongata.
Spinal Cord- continuous with the medulla oblongata, there are 31 pairs of spinal nerves arise from the cord. It consists of a central area of Grey matter and an external layer of white matter. int he center is a central canal of fluid.
they grey is unmyelinated these neurone go to the skeletal muscles
the white matter are neurones going to the brain.
spinal reflexes: the effector neurone is stimulated by a neurone orginiating from the spinal cord.
a relay neruone links sensory and effector.
A reflex action is an immediate response to a sensory stimulus.
reflex arc:
withdrawal reflexes are for example moving rapidly away from a harmful simulus.
muscle stretch reflexes include two neruones sensory and effector. e.g knee jerk.
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