Each segment consists of the central axial ring and the outer pleurae, which protected the limbs and gills.
12.
The visceral pleurae covering the lung itself receive their innervation from the autonomic nervous system and have no sensory innervation.
13.
They are at first situated between the pleurae and the Intercostales interni, and then between the Intercostales interni and innermost.
14.
The costal and cervical portions and the periphery of the diaphragmatic portion of the parietal pleurae are innervated by the intercostal nerves.
15.
Pleural effusion, in which there is fluid abnormally present between the two pleurae of the angle between the ribs and diaphragm.
16.
Tissues that line the inside of the mouth, the esophagus and part of the rectum are composed of pleurae, and peritoneum.
17.
The thorax and pygidium are very regularly divided into up to 23 rather narrow segments, without a furrow within each of the pleurae.
18.
Infections of the lung tissue are called pneumonia, of the respiratory tract are called bronchitis or bronchiolitis, and of the pleurae surrounding the lungs pleurisy.
19.
The pleurae are two serous membranes; the outer parietal pleura lines the inner wall of the rib cage and the inner visceral pleura directly lines the surface of the lungs.
20.
When the space between the pleurae starts to fill with fluid, as in pleural effusion, the chest pain can be eased but a shortness of breath can result, since the lungs need room to expand during breathing.
