Speciation is the process by which new species form. It occurs when groups in a species become reproductively isolated and diverge. In allopatric speciation, groups from an ancestral population evolve into separate species due to a period of geographical separation.
<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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<span>Epithelial tissue is densely packed cells that used most in the area where protection is needed. This cells mostly used in skin, some with more keratin which will increase their ability to protect. In bone, the main protective layer is calcium mineral which was deposited by osteocytes. Because this bone doesn't really need more epithelial cells. Bone tissue only needs a good vascularization and connective tissue to support it.
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