How are the lungs designed in human beings to maximise the area for exchange of gases?
Answer
- The respiratory system starts from the nostrils , extending into a trachea (windpipe).
- As the trachea extends, it divides into two tubes called the bronchi which are connected to each lung.
- These bronchi further branch into numerous bronchioles , which end in small balloon shaped structures called alveoli .
- These alveoli provide a maximum area for the exchange of gases to occur. Being surrounded by thin walls and blood capillaries, the exchange of gases is most effective here.