Would it be possible to breathe helium instead of oxygen and would take much alteration the human body make this possible?

While it is possible to breathe helium for short periods, it is not possible to breathe it instead of oxygen.

Here's why:

1. Helium is a non-respiratory gas.

Respiration is inhaling oxygen and exhaling carbon dioxide. Helium, on the other hand, is a non-respiratory gas, which means it cannot support respiration. Oxygen is essential for the body's cells to produce energy, and without oxygen, the body's cells would quickly die.

2. Helium has a lower density than air.

Because of its lower density, helium would rise rapidly in the lungs, pushing out the oxygen-rich air. This would cause a condition known as hypoxemia, which is a deficiency of oxygen in the bloodstream.

3. Helium does not readily dissolve in the bloodstream.

Oxygen dissolves easily in the bloodstream and can then be transported to the body's cells. Helium, on the other hand, does not readily dissolve in the bloodstream, which means that it cannot be transported to the body's cells.

Although helium can't replace oxygen in the human body, it does have some medical uses. Helium is used as a breathing gas for scuba diving because it is less dense than air and therefore reduces the amount of energy required to breathe underwater. Helium is also used in medical imaging, such as MRI scans, to improve the quality of images.