1. No credible source
2. Check if its a biased answer
3. Examine evidence
The precambrian era makes up about 90% of the earths history, but there was little to no living organisms at the time other than microscopic ones. The first eukaryotes were found in the cambrian period after the precambrian period, not only that but at the end of the precambrian era in the Proterozoic era there was a mass extinction of about 70-80% of all living organisms
Answer:
1. filtration , reabsorption , secretion .
2.kidney , ureters , bladder , urethra , pinusia
3.artificial kidney
Explanation:
1- Bioremedation (When you add a species to an ecosystem its not native to.
2- The competition for resources increased in the ecosystem.
