Explanation:
they are all related to CO2 in a way
Parietal cells within the stomach lining secrete hydrochloric acid that lowers the pH of the stomach. A low pH (1.5 to 2) activates pepsin. Acetylcholine, gastrin, and histamine stimulate the proton pump in parietal cells to release hydrogen ions and decrease pH.
Answer:
lysosomes
Many components of the cell eventually wear out and need to be broken down and the parts recycled. This activity takes place inside the cell in specialized compartments called lysosomes.
Answer:
So where then did all the carbon that living organisms are built of come from? It turns out that most of the carbon we use today came from a collision with another smallish planet about 4.4 billion years ago.