I know its not d but it might be c or a
Go to school and find them
It is based in the Animals Kingdom hope that helps.
calcium is released into the sarcoplasm through gated channels
<h3>What is
calcium ?</h3>
The chemical element calcium has the atomic number 20 and the letter Ca as its symbol. Calcium is an alkaline earth metal that reacts with air to create a black oxide-nitride coating. Its heavier homologues barium and strontium are most similar to it in terms of physical and chemical characteristics. It is the third most plentiful metal, behind iron and aluminum, and the fifth most abundant element in the crust of the Earth.
The most prevalent calcium component on Earth is calcium carbonate, which may be found in limestone and the fossilized remains of ancient marine life. Other calcium-rich materials include gypsum, anhydrite, fluorite, and apatite. The word "lime" comes from the Latin word calx, which was made by heating limestone.
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