Otic vesicle chick, invagination of the otic placode occurs passively due to the movements of the surrounding placode. The otic placode in zebrafish, on the other hand, occurs by cavitation; the ectodermal placode condenses and forms an ovoid ball directly below the embryo surface. Otic vesicle formation occurs later, during the 25-30 somite stage in mice. Otic vesicle Otic vesicle, or auditory vesicle, consists of either of the two sac-like invaginations formed and subsequently closed off during embryonic development. It is part of the neural ectoderm, which will develop into the membranous labyrinth of the inner ear. This labyrinth is a continuous
Limb (anatomy) feet are specialized for two-legged locomotion – most other mammals walk and run on all four limbs. Human arms are weaker, but very mobile allowing us to reach at a wide range of distances and angles, and end in specialized hands capable of grasping and fine manipulation of objects. Limb (anatomy) A limb (from the Old English "lim"), or extremity, is a jointed, or prehensile (as octopus arms or new world monkey tails), appendage of the human or other animal body. In the human body, the upper and lower limbs are commonly called the arms and the legs, respectively. Arms