The respiratory system mainly consists of the lungs. The lungs give oxygen to the body, when you inhale air. They are responsible for removing carbon dioxide from the body. The circulatory system mainly consists of the heart. The heart pumps blood through the body, giving us oxygen. The heart is responsible for pumping blood and creating new blood cells. If we did not have a heart then there would be no blood, therefore, no oxygen. If you think about it, the body's oxygen transport system takes oxygen to the working muscles, through the circulatory and respiratory systems working together. The main workers are the heart, blood and lungs. The whole oxygen transport system works in a cycle.
It is d because there is always sun unless you are inside
Stress is an inevitable part of life. If stress is just in small doses, it can be of help yet if it would be big already affecting one's physical and mental function then it becomes dangerous. Having too much stress can give negative feelings such as anger and depression leading then to be at risk of having health problems such as headaches, high blood pressure, heart problems,stroke and sometimes death which then Sammy can have since he is experiencing a lot of stress at his job.
