Explanation: The government provide us with physical activity guidelines in which we are directed to perform a particular type of physical activity in order to stay fit according to our age group. We all know that obesity is one of the major cause of multiple diseases. A person with excessive weight can not expect to have a good health. These guidelines specify the types and amount of exercise necessary for everyone from different age groups not only to lose weight but to stay active and lead a healthy life.
Oxygen passes from inside the alveoli through the thin walls and dif- fuses into the blood. At the same time, carbon dioxide waste passes from the blood into the alveoli.
