Final answer:
Your body stores oxygen in the bloodstream, predominantly in the form of oxyhemoglobin. The lungs cannot store oxygen for several hours, and both oxygen and carbon dioxide are crucial for bodily functions, including respiration and pH balance.
Step-by-step explanation:
In addressing the statements provided, it's important to understand the role of oxygen in the human body and how it is transported through the bloodstream. The correct statement is 'Your body stores oxygen in your bloodstream.' The lungs cannot store several hours worth of oxygen; instead, your body relies on continuous breathing to supply oxygen to the tissues. It is true that the body needs carbon dioxide to function properly as it plays an essential role in regulating the urge to breathe and maintaining the acid-base balance in the blood.
Oxygen enters the lungs and then passes through the alveoli into the blood, where the majority is bound to hemoglobin within red blood cells. This oxygen-hemoglobin compound, known as oxyhemoglobin, is then transported throughout the body to where it is needed. Conversely, carbon dioxide is a byproduct of cellular respiration and is transported from the tissues back to the lungs via the blood, where it is then exhaled.
Your body stores a small amount of oxygen in the blood dissolved in plasma, but this is a very minimal amount and certainly not enough to last more than a few minutes without respiration. The body does not store oxygen in any significant capacity that would allow for hours of survival without breathing.
In summary, your body does store oxygen in the form of oxyhemoglobin in the bloodstream and carbon dioxide is indeed necessary for the proper functioning of your body, especially in the regulation of breathing and maintaining pH balance.