Answer:
The Sulfur Cycle.
Explanation:
Sulfur is an essential element for the macromolecules of living things. As a part of the amino acid cysteine, it is involved in the formation of disulfide bonds within proteins, which help to determine their 3-D folding patterns, and hence their functions.
I’m not exactly sure what you mean, but the diaphragm is a muscle that aids in the breathing process.
After all this info you have given me, the correct one is Keystone species. As defined in sources like National Geographic, <span> These are types of plants or animals that play a unique and crucial role in the way an ecosystem functions. Without </span>keystone species<span>, the ecosystem would be dramatically different or cease to exist altogether. I hope this helps you a lot </span>