To signal hunger, the physiological need for food, the digestive tract sends messages to the by way of hormones and nerves.

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.

In the respiration-photosynthesis cycle shown above, what are the products of cellular respiration that belong in box 2?

Which test would show positive results for orange juice