Practise airway and alveolar anatomy, ventilation and gas diffusion using slides and plan diagrams, then apply tissue-function and smoking-disease evidence to lung function.
The trachea of the gas exchange system branches into two airways, each of which enters a lung.
Name the airways that branch from the trachea to enter the lungs.
Fig. 1.1 is a photomicrograph of a section through part of the trachea.
Fig. 1.1
In Fig. 1.1, one of the tissues in the trachea is labelled T.
Describe the structural features of tissue T visible in Fig. 1.1.
Identify structure X in Fig. 1.1 and outline the features that helped your identification. structure X=
Fig. 5.1 is a photomicrograph of a section through the lungs showing a bronchus and some alveoli.
Fig. 5.1
State the function of tissue X labelled in Fig. 5.1.
Describe how the distribution of tissue X in the trachea differs from that shown in Fig. 5.1.
Describe how the epithelial tissue, Y, is adapted for its function.
Control of heartbeat is myogenic. This means the electrical activity controlling the rhythm of a regular heartbeat begins in the heart muscle itself.
Atrial fibrillation (AF) is an abnormal heart rhythm that causes rapid and irregular contractions of the atria. Untreated cases of AF can lead to a stroke.
Oxygen and carbon dioxide are also exchanged between blood capillaries and alveoli in the lungs.
The gas exchange system has specialised cells to prevent harmful microscopic particles that are present in inhaled air from reaching the alveoli.
These particles are associated with many respiratory diseases.
Explain how specialised cells in the gas exchange system prevent harmful microscopic particles from reaching the alveoli.