Answer:
calmodulin
Explanation:
The calcium-modulated protein (calmodulin) is a calcium-binding receptor protein that modulates contractile proteins (i.e., actin and myosin proteins) of the skeletal muscle and non-muscle cells (e.g., platelets). Calmodulin binds to calcium ions (Ca2+) and subsequently activates a number of Ca2+ dependent enzymes (e.g., kinases or phosphatases), which finally activate/deactivate proteins in the calcium signal transduction pathway. Ca2+-ATPase pumps in the membranes of eukaryotic cells release Ca2+ from the cytoplasm and they are autoinhibited by low Ca2+ levels, while calmodulin-binding releases this autoinhibition and thus activates the pumps. In non-muscle cells such as platelets, calmodulin also mediates Ca2+ control of actin-myosin interaction by phosphorylation of the myosin light chain (MLC).
It's a negative feedback loop.
So maybe it's an example of how humans maintain homeostasis.
Answer:
The answer is D. Double Helix
When oxygen is scarce, pyruvic acid can accumulate and is converted to carbon dioxide and ethanol which causes formation of pyruvate to yield acetaldehyde