Which of the following substances directly binds to central chemoreceptors leading to the change of breathing?Question 3Select one:a.Oxygen.b.Bicarbonate (HCO3-).c.Carbon dioxide.d.Hydrogen ion (H+).

The substance that directly binds to central chemoreceptors leading to the change of breathing is c. Carbon dioxide.

Here's a step-by-step explanation:

1. When you breathe in, oxygen enters your lungs and carbon dioxide is expelled.
2. The carbon dioxide that is expelled comes from your body's cells as a waste product of the energy production process.
3. However, if your cells produce more carbon dioxide than can be expelled, the levels of carbon dioxide in your blood increase.
4. High levels of carbon dioxide in your blood can lower the pH, making it more acidic.
5. The central chemoreceptors in your brain detect this change in pH.
6. In response, they send signals to your respiratory system to adjust your rate of breathing.
7. By breathing faster or deeper, your body is able to expel more carbon dioxide, bringing your blood pH back to normal.

So, it's the carbon dioxide that directly binds to the central chemoreceptors, leading to a change in breathing.