An error is that the scientist did not control their variables. They had one group of people playing the game at 6, and another group playing at 12. This means that other things might have affected the scores other than what was being tested, which was caffeine.
Answer:
The fix nitrogen into free nitrogen which is a usable form. They also bring nitrogen back into the system by decomposing dead organisms.
Answer 2.
Because, they are known as nitrogen fixing bacteria. These organisms convert nitrogen in the soil to ammonia, which can then be taken up by plants. After nitrogen has been fixed, other bacteria convert it into nitrate, in a process known as nitrification.
Both answer is correct choose the best choice for you.
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Answer
The worm gets coated with antibodies, which activate other cells in the immune system to secrete chemicals that kill it.
Explanation:
Production of T-helper I cytokines like IFN gamma, IL-2 and IL-18 is highly protective against helminth infection by activating the macrophage intracellular killers. Protection against mucosal eosinophil responses in which antiparasitic chemicals are released. Killing also involves direct cytotoxic mechanisms in which T- cell and NK-cells directly release antiparasitic agents like perforin and granulysin which kill the parasite.
Steroid hormones easily diffuse through the cell membrane. The hormone binds to its receptor in the cytosol, forming a receptor–hormone complex. The receptor–hormone complex then enters the nucleus and binds to the target gene on the DNA.