all which pressure is high systolic or diastolic
Pressure. Give reasons.
what benefits does the heart get from double circulatory system?
Answers
Answer:
To understand the critical importance of the heart requires taking a step back so we understand the needs of each cell in our body. Remember that our body is composed of over 10 trillion cells that work together in remarkable unity (a lesson in good governance!). Cells have basic needs, and at the top of the list would be these four things:
1) access to oxygen
2) a source of glucose
3) a balanced fluid environment with the right amount of water/electrolytes
4) removal of waste (such as carbon dioxide)
Consider how this compares to basic human needs: breathing air in and breathing out, eating food, drinking water, and getting rid of urine/stool. When you really stop and think about it, many of the things that we do can be traced back to our cellular needs.
The lungs are composed of a few hundred million tiny air sacs called alveoli, each of which are surrounded by a network of blood vessels (capillary bed) which carry deoxygenated blood, shown in blue, and carry out oxygenated blood.
Now let’s follow a single breath of air. 21% of the molecules in this breath are oxygen molecules, and as they race down into the lungs, they end up in the alveoli which are tiny air-filled sacs. The story could end there, if not for the remarkable nature of lungs. The lungs allow the oxygen molecules to continue their journey from the gas phase into a new liquid phase. Meanwhile carbon dioxide molecules make the opposite trip from liquid to gas similar to what happens at the surface of a carbonated beverage. The oxygen diffuses (think of the drop of ink in a pool of water) into the fluid interstitial space of the lung, and is then absorbed into the blood stream, and then enters into the red blood cells themselves. This diffusion occurs in a fraction of a second because the distance between the alveoli and the red blood cell is so tiny.