Search results
Results from the WOW.Com Content Network
The skull of the leopard seal. The leopard seal has a distinctively long and muscular body shape when compared to other seals. The overall length of adults is 2.4–3.5 m (7.9–11.5 ft) and their weight is in the range 200 to 600 kilograms (440 to 1,320 lb), making them the same length as the northern walrus but usually less than half the weight.
Distribution of rods and cones along a line passing through the fovea and the blind spot of a human eye [7] Most vertebrate photoreceptors are located in the retina. The distribution of rods and cones (and classes thereof) in the retina is called the retinal mosaic. Each human retina has approximately 6 million cones and 120 million rods. [8]
An ipRGC, shown here as a complied image of the retina from proximal inner nuclear layer to the ganglion cell layer with fluorescent labeling of melanopsin Spectral sensitivities of the photoreceptors in the human eye. [4] Compared to the rods and cones, the ipRGCs respond more sluggishly and signal the presence of light over the long term. [5]
The retina uses "cones," a specific type of photoreceptor, to differentiate color, according to the American Academy of Ophthalmology. Human eyes have three types of cones: red-sensing, green ...
The pupil of the human eye can range in size from 2 mm to over 8 mm to adapt to the environment. The human eye can detect a luminance from 10 −6 cd/m 2, or one millionth (0.000001) of a candela per square meter to 10 8 cd/m 2 or one hundred million (100,000,000) candelas per square meter.
The inner segment contains organelles and the cell's nucleus, while the rod outer segment (abbreviated to ROS), which is pointed toward the back of the eye, contains the light-absorbing materials. [3] A human rod cell is about 2 microns in diameter and 100 microns long. [5]
Visual phototransduction is the sensory transduction process of the visual system by which light is detected by photoreceptor cells (rods and cones) in the vertebrate retina.A photon is absorbed by a retinal chromophore (each bound to an opsin), which initiates a signal cascade through several intermediate cells, then through the retinal ganglion cells (RGCs) comprising the optic nerve.
The second most common type responds the most to light of yellow to green medium-wavelength, peaking at 530 nm. M cones make up about a third of cones in the human eye. The third type responds the most to blue short-wavelength light, peaking at 420 nm, and make up only around 2% of the cones in the human retina.