During respiration exchange of gases take place in
During respiration exchange of gases take place in
- trachea and larynx
- alveoli of lungs
- alveoli and throat
- throat and larynx
Answer
An alveolar sac is made up of simple squamous epithelium and is surrounded by blood capillaries. Thin walls and increased surface area favor the gaseous exchange which takes place between the oxygen rich alveolar air and the carbon dioxide rich blood in the capillaries at alveolar surface. Oxygen diffuses across the alveolar and capillary walls to enter the bloodstream, while carbon dioxide diffuses from the blood across these walls to enter the alveoli.
The correct option is B.