Astrocytes, <span>Star-shaped cells that anchor small blood vessels to neurons.</span>
F is the symbol for fluorine which is a single atom. A molecule is two or more atoms together, which makes F not a molecule.
<span>Activation energy refers to the amount of energy required by certain chemicals for them to have a reaction.
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Answer: This is a positive feedback loop.
Explanation:
The protein digestion in the body is an example of the positive feedback. The gastric secretions is stimulated chiefly by the action of three chemicals.
These chemicals are acetylcholine, histamin and gastrin. These chemicals stimulate the parietal cells to secrete HCL and intrinsic factors.
The chief cells secrete pepsinogen in response to the gastrin and ACh. As the dietary proteins are digested, it breaks down the amino acids and peptides.
This stimulates the G cells of the stomach to secrete more gastrin. This is how the positive feedback loop for the protein digestion works.
