The location that should have lowest oxygen concentration would be the tissue because it is the furthermost location.
Other location with lowest oxygen concentration should be in the right part of the heart. It is when all unoxygenated blood pooled before going to the lungs. But the left part of the heart will have highest oxygenated blood, so it's ambiguous.
High oxygen concentration should be found in the environment, lungs, and the blood.
The basic components of a mature mammary gland are thealveoli<span> (hollow cavities, a few millimeters large) lined with milk-secreting cuboidal cells and surrounded by myoepithelial cells. These </span>alveoli<span> join to form groups known as </span>lobules. Eachlobule<span> has a lactiferous duct that drains into openings in the</span>nipple<span>.
Hope it helps u
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Answer no 1 is correct :)
