Question

what do you exactly mean by excretion? does only kidney responsible for all type of excretion in humans​

Answer 1

Excretion :

• Excretion is the biological process by which an organism removes harmful metabolic waste from the body.

• The mode of excretion is completely different in unicellular and multicellular organisms.

Unicellular organisms :

• Waste products produced by cellular metabolism and diffused into the surrounding water through general body surface .
• Example - Amoeba and Paramecium.

Multicellular organisms :

• Specialised organs perform the function of excretion.
• Example - Flame cells ( planaria ), nephridia ( earthworms , uric acid ( birds , urea ( humans ) etc.
• Ammonia is water soluble waste product excreted by aquatic animals.

Excretion in Human beings :

• The main function of human excretory system is to remove nitrogenous waste such as urea from the body.

• It includes a pair of Kidneys, a pair of ureters, urinary bladder and urethra.

• Kidneys are located in the abdomen one on either side of the backbone.

• The purpose of making urine is to filtrate out waste products from the blood.

• This waste are removed from blood by Kidneys and are passed down to the urinary bladder by a pair of ureters.

• The urethra for the release is the urine out from the body.

• So, kidney is not the only one who is responsible for all kind of excretion in our body.

• Kidney is only responsible for removing excess of water from the body and nitrogenous waste.

Answer 2

This is the job of the excretory system. You remove waste as a gas (carbon dioxide), as a liquid (urine and sweat), and as a solid. Excretion is the process of removing wastes and excess water from the body. Recall that carbon dioxide travels through the blood and is transferred to the lungs where it is exhaled.