. . . and turning the cut sruface toward you illustrates the interior of the endodermally-lined pharynx. The buccopharyngeal membrane begins to break down at this stage to allow continuity between pharynx and the stomodeum (primitive oral cavity).

                     Species: Mouse 
                     Day Gestation: 9 
             Approx. Human Age: 28 days 
                                   View: Lateral 
                Pharyngeal Arches
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