The respiratory system - The pleural membranes

Question 1

What are the pleural membranes made out of?

Answer 1

. They consist of a serous membrane – a layer of simple squamous cells, supported by connective tissue. This simple squamous epithelial layer is also known as the mesothelium.

Question 2

What does the inner visceral pleura line?

Answer 2

Each lung

Question 3

What does the outer parietal pleura line?

Answer 3

Covers the thoracic cavity, diaphragmatic surface and mediastinum

Question 4

What is between the pleural membranes?

Answer 4

Pleural cavity - a fluid-filled cavity

Question 5

What can the outer parietal pleura be divided into?

Answer 5

• Mediastinal pleura – Covers the lateral aspect of the mediastinum (the central component of the thoracic cavity, containing a number of organ).
• Cervical pleura – Lines the extension of the pleural cavity into the neck.
• Costal pleura – Covers the inner aspect of the ribs, costal cartilages, and intercostal muscles.
• Diaphragmatic pleura – Covers the thoracic (superior) surface of the diaphragm.

Question 6

What is the function of the pleural cavity?

Answer 6

It lubricates the surfaces of the pleurae, allowing them to slide over each other. The serous fluid also produces a surface tension, pulling the parietal and visceral pleura together. This ensures that when the thorax expands, the lung also expands, filling with air.