It is because that's a place where no one lives so they're safe.
<span>The four biological macromolecules are carbohydrates, lipids, proteins and nucleic acid. These macromolecules are known as polymers and are built when monomers join together by a process known as the dehydration reaction. The dehydration reaction is a chemical reaction that produces water (H2O) and the result is the covalent bonding of the two monomer molecules. The monomer molecules consist of nutrients found in the soil, as in the case of plants, and the intake of food as in the case of animals.
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I think the answer is molars
Answer: Local chemical conditions
Explanation: A Precapillary Sphincter is a smooth muscle that is located in circles around the capillaries.
The precapillary sphincter helps to coordinate blood flow to the into the capillaries by causing the capillaries to decrease the flow of blood to tissues that are dormant or not active.