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.
Answer: It will affect muscle contraction because it is needed for the formation of muscle contraction cross-bridge.
Explanation: During muscle contraction calcium binds to troponin, a protein complex that regulates muscle contraction by exposing the binding site of actin filament. Actin filament active site is where myosin head binds to, creating a cross-bridge using enzyme ATPase to speed the reaction. Calcium ion are needed to activate troponin movement, otherwise it stays in its inactive form blocking the active site of actin filament. Without calcium ions, troponin will not move and there will be no muscle contractions.