Answer:With this system, blood always flows in only one direction inside the heart. There are also valves at the bottom of the large arteries that carry blood away from the heart: the aorta and the pulmonary artery. These valves keep the blood from flowing backward into the heart once it has been pumped out.
Explanation:
Answer: Because some of the teens are always on their electronics and are too lazy to exercise.
Answer:
D. Minerals
Explanation:
regulates the activity of the heart,
brain, and nerves and is found in body tissue
Eliminating junk food and not constantly eating snacks. If you don't eat these things, you will be eating a healthy diet.
Answer:
10-20% of your daily recommend amount
