Tympanic cavity Tympanic cavity The tympanic cavity is a small cavity surrounding the bones of the middle ear. Within it sit the ossicles, three small bones that transmit vibrations used in the detection of sound. On its lateral surface, it abuts the external auditory meatus [ ear canal ] from which it is separated by the tympanic membrane (eardrum). The tympanic cavity is bounded by: It is formed from the tubotympanic recess, an expansion of the first pharyngeal pouch. If damaged, the tympanic membrane can be repaired in a procedure called tympanoplasty. Should fluid accumulate within the middle ear as the result
Plasma membrane transformation they do in rats and mice, after which they return (within the next 48 h) to form the interface of the mature placenta. Moreover, as we have also seen, there are molecular alterations in the plasma membrane during early pregnancy which have common aspects across species and here some of the large mucin molecules (such as MUC-1) are particularly instructive. Changes in the basal and lateral plasma membrane regions have also been documented in many species during early pregnancy in preparation for attachment, and these too show common aspects across species—especially some membrane junctional structures. Therefore, to highlight that membrane