Once this type of retinal detachment develops and causes symptoms, it can progress to total blindness if it is not repaired promptly. In the United States, retinal detachment is a relatively uncommon condition, affecting only one of every 10,000 Americans each year.
Gas exchange in reptiles still occurs in alveoli however, reptiles do not possess a diaphragm. Thus, breathing occurs via a change in the volume of the body cavity which is controlled by contraction of intercostal muscles in all reptiles except turtles.
The process of photosynthesis occurs not on the surface layers of the leaf, but rather in a middle layer called the mesophyll (Figure 6). The gas exchange of carbon dioxide and oxygen occurs through small, regulated openings called stomata. In all autotrophic eukaryotes, photosynthesis takes place inside an organelle called a chloroplast.