How are the conditions for efficient gaseous exchange fulfilled in mammalian lungs?
- The lungs have numerous alveoli which represent a highly folded respiratory membrane to provide a large area for diffusion of the gases.
- Lungs have a rich supply of blood which transports away oxygen from one side of the respiratory membrane to maintain a steep concentration gradient that ensures continuous gaseous exchange.
- The walls of the alveoli are thin and occur in close association with blood capillaries to reduce the distance across which the gas molecule have to diffuse.
- The alveoli are moist. This helps to dissolve the respiratory gases and facilitates their diffusion. The surface tension of the fluid also helps to keep the alveoli open to allow continuous gaseous exchange.
- The breathing movements undertaken by mammals ensure that a good concentration gradient is maintained.
CATEGORIES Bio Questions and answers
TAGS Dr. Bbosa Science
