Answer:
What sends oxygenated blood back to the heart from the lungs?
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Explanation:
The four nitrogenous bases in DNA are adenine, guanine, cytosine, and thymine. They pair A-T, G-C and when transfering with RNA, A-U, which is known as Uracil, so, the pairs would be...
ATGCT
↓↓↓↓↓
UACGA
I hope this helps!
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Answer:
A
Sound waves radiate outward from a central point.