Embryology of the Ear II (Easy to Understand)

The development of the middle and external ear explained in less than 15 minutes. For the embryology of the inner ear, tap here: https://youtu.be/G0lcRHa-JGo If you are completely new to embryology and you want to understand it quickly, this should be the first video you watch: - https://youtu.be/l5gUARhXWTY -------------------------------- Recommended Text -------------------------------- Easy Embryology is a book that is dedicated to the simplification of embryology. It is available at https://drminass.com/product/easyembryology. Contact Dr. Minass for more information. ---------------------------------------- Interact With Dr. Minass! ---------------------------------------- Website - https://www.drminass.com Email - [email protected] Patreon - https://www.patreon.com/drminass Facebook - https://www.facebook.com/M1NA55 Instagram - @m1.nass Post - Address to: Minass Parcel Locker 10106 04448 59 Penshurst Street Willoughby, NSW Australia 2068 ------------------------------------------------------------------------ SUMMARY OF THE VIDEO FOR YOUR NOTES ------------------------------------------------------------------------ The middle ear - Tympanic cavity comes from the endoderm, from the first pharyngeal pouch. - The pouch expands laterally until it touches the first pharyngeal cleft - The distal part of the pouch is the tubotympanic recess, which widens becoming the primitive tympanic cavity. The proximal part remains narrow and becomes the auditory tube aka eustachian tube - The malleus and incus come from the first pharyngeal arch - The stapes comes from the second pharyngeal arch - Tensor tympani is innervated by the mandibular branch of the trigeminal nerve - Stapedius is innervated by the facial nerve The external ear - External auditory meatus comes from the first pharyngeal cleft - The solid epithelial meatal plug will dissolve by the seventh month, otherwise the newborn will be deaf - Th tympanic membrane (eardrum) is made from three layers: ectoderm epithelium, mesoderm middle layer which is connective tissue, and endoderm which is the inner mucous membrane (epithelium). - The malleus' handle is in contact with the tympanic membrane. - The auricle develop from 6 swellings called the auricular hillocks. - Hillocks 1, 2, and 3 come from pharyngeal arch 1 - Hillocks 4, 5, and 6 come from the second arch - The hillocks will eventually grow and fuse together in a complicated process that I have simplified by just saying "they all fuse together" - 1 is the tragus, 2 is the helix, 3 is the cymba conca, 4 is the concha, 5 is the anti-helix, and 6 is the anti-tragus - lets keep it at that