Expert: Walter Hintz - 12/3/2007

Question
Hi there,
I am currently in my final weeks of my biology course. And I am at a point where going through my notes and books I did not find answers that I needed. It would be great if you could help me. I got 4 questions I did not understand.
1)In cellular respiration, ATP and Carbon dioxide are produced. How does this ATP be used by a muscle cell to effect contraction

2)How does the carbon dioxide produced is removed from the cell. This part I did not understand because I thought carbon dioxide was not even in the cell.

3)What form would the carbon dioxide transported in the blood and what route will it follow to end up in the alveoli of the lungs?

4)And lastly I did not know how did the route of the carbon dioxide follow to the atmosphere after exhalation?

I will be looking forward to  your reply. Thank you for your time.  

Answer
Hi Jeff
1.Muscle activity requires energy.  ATP contains energu in a phosphate bond.  A phosphate splits off to form ADP and energy is the result

2.It passes from the cell into the blood stream by diffusion.

3. It attaches to the hemoglobin molecule and is carried through the venous system to the lungs by way of the right heart and the pulmonary arteries

4. It is carried by vessels the the alveolia nd then diffuses into the air space in the alveoli and leaves the body during expiration. (breathing out)