3.1.1.2 The structure and functions of the cardio-respiratory system
What you need to know
Describe the process of gas exchange at the alveoli.
Explain the features that assist in gaseous exchange, including the large surface area, moist thin walls (one cell thick), short diffusion pathway, dense capillary network, and large blood supply.
Understand the movement of gas from an area of high concentration to an area of low concentration.
Explain how oxygen combines with haemoglobin in red blood cells to form oxyhaemoglobin.
Identify that haemoglobin can also transport carbon dioxide.
