The heart rate increases during exercise. This increase in heart rate increases blood flow to the muscles. Explain, as fully as you can, why this increase in heart rate is necessary. pls help I am on a timer, think it is biology but not sure

Which sentence best describes the relationship between chlorophyll and the chloroplast? a.) chlorophyll is a chemical found in a chloroplast. b.) chloroplast is a chemical found in a chlorophyll. c.) both chlorophyll and chloroplasts are found in animals. d.) both chlorophyll and chloroplasts make carbon dioxide.