Genes and the environment
<span>Answer: Blood leaves the left ventricle through the aorta.
The blood that is pumped from the heart and goes through all of the body structures, that need to be irrigated, leaves from the left ventricle. This ventricle will contract and push the blood to go to the aorta. From there, goes to the rest of the body.
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Every cell of the organism has the same DNA sequence and same genes. However, not all genes are expressed in every single cell at the same time. Only those genes necessary for a specialised function of a specialised cell are expressed in the specialised cell. For example, skin cells have some different proteins than nerve cells. Genes responsible for those "skin proteins" are activated in skin cells and are turned off in nerve cells.