Hi there,

Hope you are doing good.

Please find your answer below:

• The biological process of removal of harmful nitrogenous metabolic waste from the body is called excretion.
• Unicellular organisms excrete by diffusion and multicellular organisms use specialized organ to perform same function.

For video explanation, click the link below:

https://www.youtube.com/watch?v=tAjMD3ar_tM&t=4664s [ONE SHOT VIDEO LINK]

Regards