<span>There are other avenues to find the cure to diseases that do not involve exploiting fetuses.
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When we breathe in, oxygen enters our lungs and enters small sacs in our lungs called the alveoli. In the alveoli, the oxygen diffuses INTO the bloodstream through small blood vessels, called capillaries, that surround these alveoli. The oxygen is now in our bloodstream instead of our lungs and is used in cell respiration etc.
Oppositely, carbon dioxide is diffused FROM the bloodstream TO the alveoli, also through these capillaries. The carbon dioxide is now in the lungs instead of the bloodstream and when you breathe out, the carbon dioxide is breathed out out of your lungs.
Hope this helped, even if it helped a tiny bit. :)
Bone is a type of connective tissue, with specialized cells embedded in a matrix. The matrix of bone consists of ground substance and fibers.
Hope this helps!
<span>The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds.
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<span>Ethylene is used to ripen crops so that all plants in a crop will ripen at the same time.
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