The tongue helps us in tasting things. the tongue has thousands of tiny taste buds on it this is why it feels rough. different areas of the tongue help as in tasting different kind of substance . there are four basic taste: sweets,sour,bitter,and salty.
it is the largest sense organ in the body and is water proof.
it has millions of tiny nerve endings. the nerve ending help as to feel the sensation of pain, heat,cold,pressure,ETC. it protects the internal organs against infection, injury and harmful sun rays. the skin also has millions of tiny holes called pores. it is
through the pores that sweat is excreted . sweat is a waste product consisting mainly of water along with dissolved salts . sweating brings down the temperature of our body. the salt from the sweat collects on our skins while the water evaporates. the salt can be removed by bathing regularly.
THE NOSE help to a smell of verity or object from fragrant perfumes to stinking drains. the inner side is lined with small hair which act as filters trapping dust particles from entering in.
the senses of smell and taste are closely linked. when we are down with a cold, the nerve endings get blocked. this is why we cannot smell thinks properly nor can we taste our food well.
these are the sense organs which help us to hear sound around us. Ears also help us to keep our balance the ear has three major parts -outer, middle and inner. in mammals the outer ear is just an external flap called PINNA.
the nervous system
if your hand accidentally touches the hot lid of a vessel. what is your reaction? this instant reaction without any apparent thinking on your part is brought about by the nervous system . the nervous system is made up of special cells called NEURONS
or the nerve cell the nervous system help us to react to our surrounding . it also help us to think, learn and remember thing
the human brain has three parts
man is the most intelligent animals on the Earth. what makes him stand apart from all organisms is his highly developed brain. it keeps the body working smoothly and looks after thought,fillings,and memory. the brain helps man to get massages, take decisions and send massages.
•it controls our body movements.
•Helps us to store information in our heads.
Cerebrum – is the largest part of the brain.
it is the area where all the sensory impulses (signals) are received and despatched. it is also responsible for learning memory, intelligence and various emotions such as joy, sorrow etc.
Cerebellum – lies below the posterior part of the cerebrum. it is responsible for co- ordination of movement and for maintaining the balance of our body while walking, running dancing etc…..
Medulla – connects the brain to the spinal cord. it control certain vital involuntary or reflex action such as breathing ,heart beat
WHAT IS A REFLEX ACTION ?
an instant reaction (Automatic)shown by the body to protect oneself from injury is known as reflex action. a true reflex action is an automatic response over which the individual has no control . we are quite unconscious of most of our reflex action .