Anatomy Physiology Of The Special Senses

After being shown a picture of an elephant they eye will take the light that is reflected from the object and it will enter the eye through the pupil. Then the light will be focused by the cornea and the lens to form a sharp image of the elephant in the retina. The retina is the network of neurons that cover the back of the eye and contains the visual receptors for a person vision. The visual receptors are made up of cones and rods that contain light sensitive chemicals called visual pigments. Visual pigments reacht to light and cause a triggered electrical signals to occur. These electrical signals will then flow through a network of neurons and this network of neurons is what makes up a persons retina. After the flow through the network of neurons occurs the electrical signals will emerge from the back of the eye in the area

When it comes to vision, we see things based on the light reflected from surfaces. The reflected light waves enter the eye through the cornea at the front of the eye, it's resized at the pupil, focused by the lens, and hits the retina at the back. The light is then detected by rods and cones, photoreceptors, which alters the light into electrical signals. The optic nerve transmits those vision signals to the lateral geniculate nucleus, where visual information is transmitted to the visual cortex of the brain then converts into the objects that we see.

The retina is what houses the eye’s rods and cones. The eye has about 6 million cones and 120 million rods. Both rods and cones get their names from their shape. Rods do not provide color vision, and are sensitive to dim light. Cones function well in the day and provide color vision.

The eyeball holds many parts to allow eyesight. The retina holds the key to allowing the human eye to see color. The pupil appears as the black part of the eye that people see, the pupil however does not have much to do with comprehending color. As Clarence Rainwater said in his book “The pupil is simply the hole in the iris through which light enters the eye.” (84) The light then has to pass through many parts of the eye before reaching the retina such as the transparent cornea, the aqueous humor, the lens, and the vitreous humor. Clarence Rainwater described the retina as “... the eye’s sensitive inner surface.” (86) The exciting part of the eye starts here. The retina holds the key as stated by Clarence Rainwater, “... a complex system

There are two cells in the retina that determine how well we see color, shapes and detail. The rods, which are located in the retina, are responsible for our vision in low light. They do not facilitate color vision, and have a low spatial awareness. The cones react in higher light levels and are responsible for color and details, as well as depth perception. When the light hits the rods and the cones a chemical reaction occurs giving us our vision.

Cone cells are used for color vision while rods are used to see in black and white. The cone cells can pick up 3 basic colors; red, green, and blue. When they pick up light, photosensitive chemicals in the outer part of a cell release a electrical charge, allowing the brain to precieve the light as color. They use different groupings of these colors

However, at its head, there is a blind spot because there are no photoreceptors in this part of

The eye is made up of three layers. The outermost layer is called the fibrous tunic and is composed of the cornea and sclera. The middle layer is named the vascular tunic or uvea. This layer consists of the choroid, cillary body, pigmented epithelium, and the iris. The innermost layer is the retina, and it receives oxygen from blood vessels of the choroid and retinal vessels. Spaces of the eye are filled with the fluid aqueous humor. This fluid is found between the cornea and lens of

When the photoreceptors are stimulated they transmit impulses to the bipolar cells that project to the ganglion cells of retina.

The visual system of the cells within the brain contain an area known as the receptive field and is the point in which light enters hits the cell of a receptor (Kalat, 2013). This part of the visual system relies on sensory information, such as light, to either excite or inhibit the cells within the center portion of the receptive field. One of the most significant processes of transmitting information from the visual field is through primary cells of the visual receptors, which include the retinal ganglion cells. In the retina, ganglion cell send information from the eye to the brain. Both the rods and cones within the visual system have a rather small receptive field that connects to bipolar or amacrine cells, of which have their own receptive field consisting of ganglion cells, and then the ganglion cells ultimately make up a larger receptive field (Kalat, 2013).

The optic nerve reaches from behind the eyes to the occipital lobe where this visual information can finally be interpreted into what we know as ‘seeing something’. It is at this point that it is useful as this is when colours can be perceived (Breedlove, 2010).

The next structure of the eye is the retina it is responsible for the viewing of images in other words it is responsible for your ability to view the external environment around you. The retina which is the “third stage of the eye” (Segre, 2015) is essentially a light-sensitive tissue. The functions of the retina mirror that of a camera 's film roll in which the retina sends a stream of chemicals which move from various areas of the eye eventually creating the image that you see. The entire retina not only refers to one structure but to multiple structures.According to (Segre, 2015) These include the photoreceptor cells which are subdivided into two groups those of which include rods and cones. The rods when it comes to detection are on a different level in comparison to the cones because the light sensitive pigments that are located inside the rods of the retina are much more sensitive they capture more light and they are able to amplify the stimuli and incoming impulses to a greater extent than cones are able to. This was shown according to Baylor (2014), in an experiment conducted in which it was found that only one photon cell possessed the ability to emit a response from a rod but concerning this same experiment it was shown that hundreds of photons were needed in order to emit even a small response from a cone. Concerning the cones though in terms of spatial and temporal resolution they tend to perform better this may be due to the fact that there is a large number

The next step to vision is very important, and it is called transduction. Transduction is how light energy is turned into electrical signals that can be interpreted and understood by the brain. Transduction happens primarily in the retina, which is made up of several layers of cells. The first layer that light goes through is made up of rods and cones. Rods are on the outside of the retina and cones make up the center, called the fovea. Rods can only see black and white, while cones can only see color. This was really interesting to me because I did not know that different parts of our eyes interpreted different color light. I thought all light was that same to our eyes, but this is not the case. Since, rods are on the outside of the retina, this means we can see black and white better with of our periphery vision. When light hits our photoreceptors, which are the rods and cones, it activates the photopigment called rhodopsin. It then sends the information to the second layer of cells in the retina called the bipolar cells. The bipolar cells then pass on