The myocardium receives its blood supply from the coronary arteries.

The coronary arteries provide the main blood supply to the heart. The coronary arteries also supply the myocardium with oxygen to allow for the contraction of the heart and thus causing circulation of the blood throughout the body.

Explanation:

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"d.) carbon dioxide and hydrogen sulfide"

nucleic acid molecules are incredibly complex, containing the code that guarantees the four different nucleotide units comprise dna, the nucleic acid of interest to the genealogist. and one of four nitrogen-containing molecules called nucleotides