Answer:
Explanation:
Helium is the second most abundant element in the universe, but here on earth, it's rather rare. Most people guess that we extract helium from the air, but actually we dig it out of the ground. Helium can be found in certain parts of the world, notably in Texas, as a minor component in some sources of natural gas.
Helium is generated underground by the radioactive decay of heavy elements such as uranium and thorium. Part of the radiation from these elements consists of alpha particles, which form the nuclei of helium atoms. ... Helium can also be produced by liquefying air and separating the component gases
When the gas contains more than about 0.4% helium by volume, a cryogenic distillation method is often used in order to recover the helium content. Once the helium has been separated from the natural gas, it undergoes further refining to bring it to 99.99+% purity for commercial use.
The answer to your question is:
C. 22 pairs of autosomal chromosomes, 1 X chromosome, and 1 Y chromosome.
I hope this helps!
Answer:
False
Explanation:
The papillary muscles of both right and left ventricles began to contract shortly before the other ventricular muscles (systole) so that they can take up the slack on the chordae tendineae as the full force of ventricular contractions sends blood against the atrioventricular (AV) valve flaps.
They prevent the backward flow of blood to atria from ventricles. So if they contract after the ventricle systole they would not be able to perform their job.
