I believe it’s A. Birth control patch
Negative: 1:we become lazy.
2:our body become's weak where as we are the bodybuilders.
3:sperm's problems in human's
positive:1:made the life easier
2:saves time
3:electronic's become less expensive..
Answer:
The reason is because the heart requires more oxygen when exercising. Several physiological events happen to increase the blood flow and therefore oxygen flow to that muscles,including the heart.
Also the volume of blood that the heart pumps out is maintained so that the body organs receive the necessary amount of oxygen and nutrition, because if it didn't adjust the flow of blood to match activity level, you will be insufficient. Either output method will be lower than needed.
The cells in the heart need a constant supply of nutrients / oxygen and to get rid of their waste products ans that why it needs its own special circulatory system.
Go to other doctors. Research on reliable websites.
