4 TracheaThe trachea lead from the throat to the lungs At the base of the trachea lie the bronchiCartilage is present in the trachea in the form of C shaped rings This helps to stop the airways collapsing or bursting as pressure changesTrachea on the leftOesophagus on the right
5 BronchiThe bronchi are at the bottom of the trachea They then branch further into bronchiolesBronchi contain irregular blocks of cartilageThe cartridge keeps the bronchi open
6 Bronchioles Bronchioles These are smaller branches They do not contain CartilageThey are made of smooth muscle (which contracts if you have asthma)This can contract or relax and thus control the diameter of the airways….Not having cartilage present allows this to happen
7 Alveoli Alveoli are present at the end of the bronchioles Thin epithelial tissue. 1 cell thickElastic fibers allow stretchingWell vascularised
8 Protection-the goblet cell Goblet cells are present in the trachea and bronchi Pseudostratified Epithelium Produces mucin-glycoprotien-sticky traps particles
9 Protection- CiliaCilia are present They beat and carry the mucus upwards 1cm/min… Speedy Slime! Enters stomach and destroyed
10 Protection-Macrophages Macrophages are present They are phagocytes They mop up bacteria and dust When you have an infection other phagocytes will join them
11 SummaryWe have now reviewed Gross structure of the gas exchange system Fine structure of the gas exchange system How the structure of the gas exchange system relates to it’s function.