72-hour Chick Embryo Small Image Menu Instructions: The images on this menu will take you to a series of sub-menus containing more small-sized images such as these. From the sub-menus, you will be able to choose which full-size images you would like to view.
This page on the embryology in chicken relates to the following: • Whole mount preparation 72 hours, with a detail view on the development of the head () • Cross sections 72 hours; eye and heart formation ( ) Stage 72 hours Whole-mount preparation 72 hours after fertilization Information: 72 Hours after fertilization, the rotation of the embryo to the left is arrived such behind the region of the heart and only the caudal part of the embryo must twist 90 degrees. The two flexures in the head region are almost completed. The fourth pharyngeal groove develops and the pharyngeal arches are thicker. Due to the cranial flexure, the pharyngeal region (= region of the trachea) is now located at the ventral side of the head. The fore and hind limbs at the level of the 16 th to the 20 th respectively the 27 th to the 32 th somite pairs are visible as small buds at an incubation time of about 3 days.
Embryology of chicken 72 hours after fertilization: stained whole-mount preparation. 1 = Auditive (otic) vesicle, 2 = Myelencephalon, 3 = Metencephalon, 4 = Amnion, 5 = Mesencephalon, 6 = Optic vesicle + lens, 7 = Diencephalon, 8 = Epiphyse, 9 = Telencephalon, 10 = Branchial arches, 11 = Heart, 12 = Forelimb (wing) bud, 13 = Vitelline arteria/vein, 14 = Hindlimb (leg) bud, 15 = Tail Information: The development of the brain is shown at higher magnification. The further development of the five brain vesicles (telencephalon, diencephalon, metencephalon, mesencephalon and myencephalon) in to the different head structures is clearly visible.
This product is licensed for non-commercial use only. Torrent picbasic pro 3 free. Use of the Student Edition in a business or for creation of products that are sold for profit is prohibited. Licensed users of the Student Edition may upgrade to the Silver* or Gold Editions with a discount equal to the purchase price of the Student Edition. Three different device architectures are represented.
The eye vesicles differentiate as two lateral projections of the diencephalon and come in contact with the external layer (ectoderm) to form the optic cup (neurectoderm) and the lens (ectoderm). The dorsal projection of the dieencephalon is also visible and will differentiate in to the epiphysis (epi= at the upper side).
The depression at the ventral side of the diencephalon develops in to the hypophysis ( hypo= under; not visible in this fig.). The auditory vesicles develop at the level of the myencephalon. Embryology of chicken 72 hours after fertilization: detail of the head in a stained wholemount preparation 1 = Auditive (otic) vesicle, 2 = Myelencephalon, 3 = Metencephalon, 4 = Amnion, 5 = Mesencephalon, 6 = Optic bulb, 7 = Lens, 8 = Diencephalon, 9 = Epiphyse, 10 = Telencephalon, 11 = Olfactory groove Cross sections 72 hours A. Eye and heart formation: left wholemount and right cross section (dorsal part oriented to the left) 1 = Spine, 2 = Dorsal aorta, 3 = Foregut, 4 = Heart formation, 5 = Lens, 6 = Optic vesicle, 7 = Diencephalon, 8 = Heart region, 9 = head B. Heart formation: left wholemount preparation and right cross section (dorsal side oriented to the left) 1 = Spine, 2 = Dorsale aorta, 3 = Pleural cavity, 4 = Foregut with folding of the lung bud, 5 = Sinus venosus, 6 = Truncus arteriosus, 7 = Atrium, 8 = Regio cerebrale hemisphere of the telencephalon, 9 = Diencephalon, 10 = Olfactory groove, 11 = Heart region, 12 = Head region.
The mechanisms of development of posterior levels of neural tubes of chick embryos were analyzed by study of serial cross‐sections of a continuous series of normal embryos between 40 to 72 hours of incubation. Two extirpation experiments were performed in ovo on other embryos of the same stages. Descriptive studies revealed the presence of an overlap zone in which two types of neural tube formation occurred. Open neural tube formation (by fusion of neural folds) occurred dorsally in this region; closed neural tube formation (by canalization of solid medullary cord tissue) occurred ventrally.
Extirpation of the posterior end of the neural plate produced defects within the lumbosacral region, indicating that the posterior neural plate participates in the formation of the lumbosacrum, and that the overlap zone is therefore in the lumbosacral region. Extirpation of the prospective neural tissue in the anterior end of the tail bud indicated that only the most posterior levels of the neural tube originate exclusively by cavitation of the tail bud. In both extirpation experiments a neural tube formed independently within the tail bud tissue, indicating that formation of the neural tube in this region is not dependent upon direct continuity with neural tissue anteriorly.