Without a nucleus, multicellular life forms, called eukaryotes, would not exist. According to the Molecular Expressions , the nucleus acts as the administrative center and information processor for the cell by storing its genetic material and coordinating its activities.
Answer:
The immune system responds to antigens by producing cells that directly attack the pathogen, or by producing special proteins called antibodies.
Explanation:
Specific immune responses are triggered by antigens. Antigens are usually found on the surface of pathogens and are unique to that particular pathogen. The immune system responds to antigens by producing cells that directly attack the pathogen, or by producing special proteins called antibodies.
The immune system review (article) | Khan Academy
Answer:
https://phys.org/news/2009-05-bird-songs-environment.html
Explanation:
