Search results
Results from the WOW.Com Content Network
The eyes begin to develop as a pair of diverticula (pouches) from the lateral aspects of the forebrain.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.
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 ...
Only the epidermis in the head is competent to respond to the signal from the optic vesicles. Both the optic vesicle and the head epidermis are required for eye development. The competence of the head epidermis to respond to the optic vesicle signals comes from the expression of Pax6 in the epidermis. Pax6 is necessary and sufficient for eye ...
A collimator sight is a type of optical sight that allows the user looking into it to see an illuminated aiming point aligned with the device the sight is attached to, regardless of eye position (with little parallax). [1] They are also referred to as collimating sights [2] or "occluded eye gunsight" (OEG). [3]
The cancer had spread to both of 1-year-old Lily Morss' eyes. ... had to have her eye removed from cancer in her retina. ... from celebrity news to compelling human interest stories.
Ophthalmic viscosurgical devices (OVDs) are a class of clear gel-like material used in eye surgery to maintain the volume and shape of the anterior chamber of the eye, and protect the intraocular tissues during the procedure.
Human eye cross-sectional view grayscale. Retinal precursor cells are biological cells that differentiate into the various cell types of the retina during development. In the vertebrate, these retinal cells differentiate into seven cell types, including retinal ganglion cells, amacrine cells, bipolar cells, horizontal cells, rod photoreceptors, cone photoreceptors, and Müller glia cells. [1]
The lens placode under the direction of the optic vesicle gives rise to the lens of the eye. The adenohypophyseal placode , which forms the anterior lobe of the pituitary gland . Other animals