Parietal cells produce gastric acid (hydrochloric acid) in response to histamine (via H2 receptors), acetylcholine (M3 receptors) and gastrin (gastrin receptors). Parietal cells contain an extensive secretory network (called canaliculi) from which the HCl is secreted by active transport into the stomach.
Answer:
The marginal cost of increasing production from 5,000 units to 6,000 would be $1,000 / 500.
Explanation:
The cell membrane allows substances to enter and leave the cell and gives the cell structure.
An example of a parallel choice on a dichotomous key is happy or sad and old or young. Either one of those answers.
