The Complex Structure of the Visual Organ of the Human Body

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

Also, on the retina is the optic disk. There are no photoreceptors in this area, so any light that falls on this part of the retina is unseen and creates what is called the blind spot. (Hugh

A medical definition of vision impairment is a sine qua non that prohibits 20/20 vision in one or both eyes (Bowman, Bowman, Dutton & Royal National Institute for the Blind, 2001; Vision Australia, 2015; Webster & Roe, 1998). Examples of vision impairment include, cataracts, which has the lens inside the eye increasingly cloudy; albinism, which is passed down genetically affecting clear vision and causes sensitivity to bright light; optic nerve damage, which affects field of vision as those nerves controlling vision are disrupted; macular degeneration, where parts of the retina that control colour and fine details are affected; retinitis pigmentosa, which is an ongoing reduction of the field of vision available and nystagmus, where the eye flickers involuntary (Bowman, Bowman, Dutton & Royal National Institute for the Blind, 2001; American Foundation for the Blind, 2015; Vision Australia, 2015 ; Baton Rouge Regional Eye Bank, 2015). John suffers from retinitis

Retinitis pigmentosa is a group of inheritable diseases that is characterized by gradual deterioration of the photoreceptors in the retina. The photoreceptor cells in the retina, rod cells, are light sensitive cells that are able to sense low levels of light. The frequency of retinitis pigmentosa is one in four thousand births (Deng et al., 2015; Fahim et al., 2012; Haddad et al., 2016; Shu et al., 2012) People affected by retinitis pigmentosa will typically exhibit symptoms of night-blindness first, and this will precede a loss in the patient’s visual acuity field that starts from the outer edge and gradually moves inward resulting in a much smaller visual field and loss of peripheral vision, also known as tunnel vision (Haddad et al., 2016).

To understand the diverse causes of RP, a basic understanding of visual perception is required. Phototransduction (conversion of light to electrical signals) occurs first, which is initiated by two types of photoreceptors: rods and cones. These two types vary in their function as rods are primarily responsible for night vision and lack sensitivity to color while cones function in color vision. Light contacts these photoreceptors, and isomerizes a retinaldehydechromophore (retinal) which is bound to varying types of opsin proteins corresponding in their reactivity to different wavelengths of light. Upon absorption of a photon of light, the chromophore 11-cis-retinal is isomerized to the all-trans confirmation, which subsequently causes a series of molecular interactions which ultimately result in the electrical response of the photoreceptors (Vugler 2010). As 11-cis-retinal is required to absorb photons of light, this compound must be regenerated, a function that is performed with the aid of nearby cells of the retinal pigment epithelium

My interest in the anatomy of the eye began when I was a small child. I was 8 years old when my father experienced retinal detachment in the first eye. I didn’t understand a whole lot of what was happening when my brother and I were whisked up and on a plane to a hospital in Portland for surgery. During the long wait, my mother began describing what was happening in my father’s eye. I remember sitting and

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

Glaucoma can occur without much warning, whether its acute from a accident in which a trauma is issued on the eye, or if it is due to age and heredity. Glaucoma doesn 't discriminate, it is seen in all races and genders. It happens so slowly with age and heredity that you don 't even notice the loss of vision until it is too late, and with acute glaucoma it can be painful with pain that radiates over the face, a headache, nausea, vomiting and seeing colored halos around lights and even blurred vision can be a few symptoms (Ignatavicius & Workman, 2013). Once you start seeing halos, and lose peripheral vision, it may be an indicator that irreversible damage to the optic nerve has happened. In this paper we will discuss the pathophysiology of glaucoma, the types of glaucoma as well as the causes for them. the issues that glaucoma can cause someone, and the treatments and interventions. We will also have a education handout to help better understand how to administer the medication, and the effects it has on the eye.

The development of the human body is an exquisite process that involves numerous complicated processes for even the smallest of body parts, including the eyes. The eyes are an extraordinarily complex organ capable of gathering information through refracted light and sending it the brain to assemble a picture. They provide the ability to see and follow a moving object and the capability to tell an approximate distance of an object. When light passes through the cornea and iris pupil, at the anterior portion of the eye, it is focused by the lens onto the retina at the back of the eye. Photoreceptor cells, which are present in the retina, detect the light and send information to interneurons which begin to sort out the information. This information is then sent to ganglion cells which transmits the final information to the brain (Sowden 199). Because the eyes have such complicated and exquisite processes, the likelihood of developmental errors occurring are possible. A large number of these developmental errors lead to congenital defects and abnormalities that effect the individual’s eye sight. Some of these defects and abnormalities can cause serious diseases and syndromes that effect more than just the eyes, but also neurological processes, facial dimorphisms, growth failure, tracheal development, and genitalia anomalies.

Phase 2: Retina is placed in the back side of the eye and it has to „collaborate“ with cornea and lens in order to provide an image for

A) Major structures of the eye include the cornea, pupil, iris, lens and retina. The cornea is responsible for the focus and entrance of light. The pupil, an adjustable opening, decides the measure of light that enters the eye. The light's brightness effects the size of the pupil meaning it will either expand or get smaller. The iris plays a role in size as it regulates the amount of light by controlling the size of the pupil. The lens is an aspect of the eye that is located behind the pupil. The function of this part of the eye is to focus light on the retina. The retina is comprised of receptors called rods and cones. The reason for the retina is to get light that the focal point has centered, change over the light into neural motions, and

The eye is a very complicated part of the body. It is not as simple as they look they have complicated mechanisms inside. There is a part of the that is like a pathway for the aqueous humor to exit the eye. The aqueous humor is behind the lens and the ciliary muscles. when the ciliary muscle are relaxed it allow the aqueous humor flow pass the lens and ciliary muscles. After it go out the puple it can exit the eye in two ways the uveoscleral or the conventual through the trabecular (TM) or conventional pathway. The uveoscleral way is seeping through the ciliary muscles. The TM is an important function of the eye. It has the scams canal which is a outlet it has K+,Na+2cl- ions that let the aqueous humor go through. This

The eye is one of the most complex organs of the human body. In the human

The eyelids are made up of four layers, the skin, muscle, connective tissue and conjunctiva. The process of vision occurs when light waves from an object, enter through the iris. Light then passes through the lens of the eye, a double convex structure that is used to focus the light, and then reaches the retina. Inside the retina are rods and cones. Rods are used to sense light and dark, and cones are used for sensing colors. Whether the light entering the eye hits the cones or rods, a signal is sent across the optic nerve to the brain where it is processed and viewed as an image. Some issues people have with eyesight are as follows. Those who are farsighted are unable to see things clearly at a short distance, compared to a long distance. This occurs when the light that enters the eye is focused behind the retina, and not directly onto it. When the cornea is not curved enough, this happens. Nearsightedness is when one can see objects clear at a short distance, but not at a longer distance, and this is often caused by a change in the cornea. A Blind spot is the location the optic disk, where the optic nerve fiber exits, and at this location there are no cones or rods, so there is a blind spot.

You live and you learn, from the moment that we breathe our first breath, we are assimilating and are acquiring information. Life changing and profound learning experiences happen before we can even speak, as children our learning process is grandiose. Harvard University published a series of summaries on Child development. One of these articles mentions that “The basic architecture of the brain is constructed through an ongoing process that begins before birth and continues into adulthood.” ("InBrief: The Science of Early Childhood Development," n.d.).