Question

how does nitrogen waste happen what is it called

Answer 1

do you need nitrogen waste in humans or...?

Answer 2

yes

Answer 3

Metabolic processes produce waste, and a great deal of this is in the form of Nitrogen
Nitrogen combines with other molecules in the body to produce toxic compounds such as ammonia
And so the animal must find a way to excrete these toxins. As we already know, this is the function of the kidneys and the rest of the renal system.
Ammonia has only one nitrogen per molecule, but it is quite toxic. It requires a great deal of water to be flushed out of the body. Animals such as fish and amphibians, which have constant access to water, have not suffered natural selection that led to more "water conservative" measures, and flush their nitrogenous waste primarily as ammonia.
Terrestrial animals, however, because they have less access to water, have been under selective pressure to "repackage" their toxic ammonia as less toxic molecules
flush those less toxic compounds with less water
Mammals metabolize ammonia into a molecule called urea
Reptiles (including birds) go one step further, packaging their nitrogenous waste as uric acid
...which contains FOUR nitrogen atoms per molecule. It requires more metabolic energy to make than urea, but it also eliminates more nitrogen per molecule and, is quite non-toxic, and requires very little water to flush from the body.
The white, crystalline substance you see in a typical bird or lizard "poop" is actually urine: a little pool of uric acid crystals in a very small amount of water.
So there are three general ways that vertebrates rid their bodies of nitrogenous waste:
ammonia - one nitrogen per molecule; highly toxic; requires lots of water to flush
urea - two nitrogens per molecule; less toxic; requires less water to flush
uric acid - four nitrogens per molecule; non-toxic; requires very little water to flush

Answer 4

Thank You so much for your help

Answer 5

no problem :]