AP BIOLOGY

Detailed explanation-1: -Because of the enormous number of alveoli (approximately 300 million in each human lung), the surface area of the lung is very large (75 m2). Having such a large surface area increases the amount of gas that can diffuse into and out of the lungs.

Detailed explanation-2: -Trachea has a large surface area for gaseous exchange.

Detailed explanation-3: -Large surface area: human lungs contain about 500 million alveoli, which creates a surface area around half the size of a tennis court. This speeds up diffusion because gases have more area over which to diffuse.

Detailed explanation-4: -Remember, the blood capillaries must be in contact with the respiratory surface for gas exchange to take place. Therefore, the greater the surface area, the more gas exchange can occur.

Detailed explanation-5: -All the structures for gas exchange have common as follows: They have a large surface area relative to the volume of the organism. They are thin and so have a short diffusion pathway. They have a moist surface where gases can dissolve first before they diffuse in or out.