The answer to this one is true
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.
Birds, unlike mammals, do not have separate exits for urine and feces. Both waste products are eliminated simultaneously through the cloaca. While mammals excrete nitrogenous wastes mostly in the form of urea, birds convert it to uric acid or guanine, which reduces water loss in comparison.
Explanation: some cells are specialized to do certain stuff. Like the breaking down of glucose wouldn't happen in the cells found in your leg.