3 is the answer because they play a key role in the nitrogen cycle.
So you want me to create environmental slogans or is this a question?
It is an example of Cyclical unemployment. hope i helped!
The process is called Peer-Reviewing. In Peer-Reviewing, scientists/academic peers "peer review" the work of a scientist to check for accuracy or any false information that might reduce the legitimacy of their study or change "how realistic/real" their study is.
p.s. This is also common sense because scientists make up an entire scientific community who base their scientific studies on consistency and accuracy.
Answer:
Trypanosoma brucei
Explanation:
T. brucei is a unicellular eukaryotic parasite that causes sleeping sickness. This organism has an elongated body, central nucleus, only an elongated mitochondria housing the kinetoplast, where the mitochondrial DNA is located; It has a scourge that gives it motility. Its undulating cell membrane, as a result of flagellar movements, is covered with glycoproteins that elicit little immune reaction, allowing this parasite to go unnoticed.
This organism infects the host by evading the host's immune system by altering its surface proteins with each generation.