You have soccer practice after school but are so hungry and tired. You decide to quickly eat a granola bar and drink a juice box to give yourself some energy. Describe how your digestive system and circulatory system will work together to provide energy to your muscles.

The digestive system works very closely with the circulatory system to get the absorbed nutrients distributed through your body. The circulatory system also carries chemical signals from your endocrine system that control the speed of digestion.

the correct answer: the index of refraction of the second medium is lower i tried this persons answer and it was wrong this person is lying

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.