Respiration and Gas Exchange Quiz

• Importance of breathing and gas exchange: Oxygen is brought into the body for respiration, which provides energy for all cells; carbon dioxide is removed.
• Gases in inhaled air: Oxygen makes up about 21%, carbon dioxide less than 1%; nitrogen, the main component, is about 78%.
• Gases in exhaled air: Oxygen decreases to about 16%, carbon dioxide increases to around 4%; water vapor and other gases in small quantities increase.
• The respiratory system: Diaphragm, a flat muscle at the bottom of the lungs, helps fill the lungs with air during inhalation and empties them during exhalation.
• Breathing process: Diaphragm moves down, rib cage expands, and lungs fill with air; reverse process occurs during exhalation.
• Lungs and respiration: Lungs receive air from the trachea; ribs and muscles surrounding them help expand the lungs during inhalation.
• Inhalation process: Diaphragm moves down, rib cage expands, and air pressure decreases, causing air to be drawn in.
• Exhalation process: Diaphragm moves up, rib cage contracts, and air pressure inside lungs increases, causing air to be expelled.
• Continuous process: Breathing process occurs 24/7.

Test your knowledge about the importance of breathing, gas exchange, and the respiratory system. Learn about the composition of inhaled and exhaled air, the processes of inhalation and exhalation, and the continuous nature of the breathing process.