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The optic vesicles project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk. [1] [2] Closure of the choroidal fissure in the optic stalk occurs during the seventh week of development. The former optic stalk is then called the optic ...
First, there is an outpocketing of the neural tube called optic vesicles. Development of the optic vesicles starts in the 3-week embryo, from a progressively deepening groove in the neural plate called the optic sulcus. Some studies suggest this mechanism is regulated by RX/RAX transcription factor. [8]
These diverticula make their appearance before the closure of the anterior end of the neural tube; [1] [2] after the closure of the tube around the 4th week of development, they are known as the optic vesicles. Previous studies of optic vesicles suggest that the surrounding extraocular tissues – the surface ectoderm and extraocular mesenchyme ...
The otic vesicles then form ventral and dorsal components. The ventral component forms the saccule and the cochlear duct. In the sixth week of development the cochlear duct emerges and penetrates the surrounding mesenchyme, travelling in a spiral shape until it forms 2.5 turns by the end of the eighth week. The saccule is the remaining part of ...
During embryonic development of the eye, the outer wall of the bulb of the optic vesicles becomes thickened and invaginated, and the bulb is thus converted into a cup, the optic cup (or ophthalmic cup), consisting of two strata of cells.
A seven-week-old human baby following a kinetic object. Infant vision concerns the development of visual ability in human infants from birth through the first years of life. The aspects of human vision which develop following birth include visual acuity, tracking, color perception, depth perception, and object recognition.
Embryonic age: Week nr 5. 4 weeks old. 29–35 days from fertilization. The embryo measures 8 mm (0.31 in) in length and weighs about 1 gram. [4] Optic vesicles and optic cups form the start of the developing eye. Nasal pits form. The brain divides into 5 vesicles, including the early telencephalon. Leg buds form and hands form as flat paddles ...
The optical vesicle (which will eventually become the optic nerve, retina and iris) forms at the basal plate of the prosencephalon. The spinal cord forms from the lower part of the neural tube. The wall of the neural tube consists of neuroepithelial cells, which differentiate into neuroblasts, forming the mantle layer (the gray matter).