Search results
Results From The WOW.Com Content Network
The macula (/ˈmakjʊlə/) [1] or macula lutea is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around 5.5 mm (0.22 in) and is subdivided into the umbo , foveola , foveal avascular zone , fovea , parafovea , and perifovea areas.
Photograph of the retina of the human eye, with overlay diagrams showing the positions and sizes of the macula, fovea, and optic disc. Perifovea is a region in the retina that circumscribes the parafovea and fovea and is a part of the macula lutea. [1] The perifovea is a belt that covers a 10° radius around the fovea and is 1.5 mm wide.
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. [ 1 ] [ 2 ] It includes the cardiovascular system , or vascular system , that consists of the heart and blood vessels (from Greek kardia meaning heart , and Latin vascula meaning vessels ).
The fovea centralis is a small, central pit composed of closely packed cones in the eye.It is located in the center of the macula lutea of the retina. [1] [2]The fovea is responsible for sharp central vision (also called foveal vision), which is necessary in humans for activities for which visual detail is of primary importance, such as reading and driving.
Parafovea or the parafoveal belt is a region in the retina that circumscribes the fovea and is part of the macula lutea. [1] It is circumscribed by the perifovea.. Photograph of the retina of the human eye, with overlay diagrams showing the positions and sizes of the macula, fovea, and optic disc
The heart is a muscular organ found in humans and other animals. This organ pumps blood through the blood vessels. [1] Heart and blood vessels together make the circulatory system. [2] The pumped blood carries oxygen and nutrients to the tissue, while carrying metabolic waste such as carbon dioxide to the lungs. [3]
The elements composing the layer of rods and cones (Jacob's membrane) in the retina of the eye are of two kinds, rod cells and cone cells, the former being much more numerous than the latter except in the macula lutea. Jacob's membrane is named after Irish ophthalmologist Arthur Jacob, who was the first to describe this nervous layer of the ...
The foveola is located within a region called the macula, a yellowish, cone photoreceptor filled portion of the human retina. Approximately 0.35 mm in diameter, the foveola lies in the center of the fovea and contains only cone cells and a cone-shaped zone of Müller cells. [1]