How does smoking affect gas exchange in the lungs?

Firstly, think of what you already know about the structure of the lungs and how that makes them so effective at their job. (Elasticity, large surface area for gas exchange, high gradient and short diffusion pathway).Draw out structure of normal and abnormal diffusion pathway to illustrate the following points Over time, smokers can develop a condition called Emphysema. Let's focus on each of the areas mentioned above to think about how gas exchange is affected in this conditionLarge surface area: pockets of alveoli are destroyed, leaving behind large air spaces. This means there is less surface area available. (Think of the lung like a sponge, in emphysema the sponge has lots of larger holes in it)Elasticity: This is reduced, meaning it is harder for the lungs to force out air containing CO2 and much of it remains in the lungsDiffusion Gradient: Because of the higher concentration of CO2 in the lungs the gradient from blood to lungs is reducedDiffusion pathway: Irritants in cigarette smoke cause inflammation of the alveoli. It takes longer for gases to cross a wider membrane, so gas exchange is slowed