Answer:
E. are found in nitrogen-fixing cyanobacteria AND are used to protect nitrogenase.
Explanation:
Heterocysts are specialized cellular compartments found in nitrogen fixing cyanobacteria. They provide the ideal anaerobic environment for nitrogen fixation since nitrogenase enzyme cant work in presence of oxygen. Hence, in a cyanobacteria both the oxygen requiring photosynthesis process and the oxygen sensitive nitrogen fixation process takes place simultaneously.
Heterocysts have an additional cell wall made of glycolipid that provides a hydrophobic barrier to oxygen. They are involved in production of nitrogenase and other proteins that are required for nitrogen fixation. They also degrade photosystem II which is responsible for producing oxygen and produce proteins which remove any remaining oxygen.
Solution:
The function of a protein is determined by its shape.
The shape of a protein is determined by its primary structure (sequence of amino acids).
The sequence of amino acids in a protein is determined by the sequence of nucleotides in the gene (DNA) encoding it.
Homogeneous chromosoms pair up
Answer:
False, major false. A galaxy is a small portion of the entire universe... it contains plants, stars, asteroids, moons are insignificant compared to it. Also, pretty much all moons are larger than planets so that wouldn't even make sense.