Page 36 - EM BIOLOGY NOTES 10TH CLASS PSR DIGITAL BOOKS

4. EXCRETION
(THE WASTAGE DISPOSING SYSTEM)

Excretion :- Lesson related 1, 2, 4 marks
Activities Question and
 The word Excretion taken from latin. videos Answers PDF
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 In latin ex means out, crenere means shift.
 Excretion is one of the life process. In this process waste un-useful and harmful products
are separated and removed from the body. (or)
Elimination of wastes from the body which are formed during diffrent metabolisms is called
excretion.
 A number of reactions take place during various metabolic activities in our body.
 In this metabolic activities many useful substances and energy are produced.
 At the same time many waste/unuseful products also formed. Such as CO , water, nitrog-
2
enous wastes, Bile pigments etc ...
 These waste/un-useful products enters into the blood.
 Blood transports these products into various excretory organs. These organs separated
and removed from the body.
S.No. Excretory organ Eliminated substances
1. Kidney  Excess water, excess minerals, nitrogenous
wastes in the form of urine.
2. Lungs  CO , water vapour through expiratic air.
2
3. Skin  Excess water, small amounts of salts, urea
in the form of sweat.
4. Liver  Bile pigments, Urochrome.
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5. Large intestine  Excess salts such as Ca , Mg and Fe .
6. Salivary glands  Small amounts of nitrogenous wastes.
7. Lacrimal glands  Small amounts of nitrogenous wastes, salts
etc....
 Kidneys are the main excretory organs in the human body.
 Lungs, Skin, Liver, Large intestine, Salivary glands, Lacrimal glands are the accessory
excretory organs.
 Excretory system maintains homeostasis (ionic balance)
 Human excretory system :-
 Human excretory system contains a pair of kidneys, a pair of ureters, bladder and urethra.
Kidney :

LOCATION OF KIDNEYS EXCRETORY SYSTEM

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