The Human Eye (Functions, Parts, Disorders) PDF

the Human Eye GROUP I Abastas, Amores, Macabinguil, Pabalan  the human eye (Functions, Parts, disorders)  the human eye gathers visible light from the DID YOU KNOW? environment and convert it The Human Eye into a struc...

the Human Eye GROUP I Abastas, Amores, Macabinguil, Pabalan  the human eye (Functions, Parts, disorders)  the human eye gathers visible light from the DID YOU KNOW? environment and convert it The Human Eye into a structure that your brain can employ to produce gives you a field of vision view about 200 helps in visualization degrees wide and helps in light, color, and 135 degrees tall. depth perception Anatomy & Structure Of the Human Eye Retina Sclera Cornea Retinal Blood Vessels Hyaloid Canal Pupil Iris Optic Nerve Lens Vitreous Body IRIS the colored part of the eye that surrounds the pupil thin and strongly pigmented structure that determines eye color controls the size and diameter of the pupil IRIS PUPIL According to National Cancer Institute, The pupil is the circular aperture in the middle of the iris (which is the pigmented tissue that gives the eye its "eye color" in front). The pupil changes size to PUPIL let light into the eye. SCLERA As per Cleveland Clinic, The sclera is the white part of the eye. Its a strong tissue that acts as a covering that wraps around the eyeball maintaining its perfect circle shape and protecting it from foreign bodies and injury. SCLERA CORNEA It acts like a barrier against dirt and germs, and it helps filter out some of the sun's damaging ultraviolet light. As light enters your eye, it gets refracted, or bent, by the cornea’s curved edge. This helps determine how well your eye can focus on objects close up and far away.  Layers of THE cornea 1. Epithelium: Outer layer; protects from chemicals, water, and microbes, absorbs nutrients from tears and oxygen. It’s the most sensitive part. 2. Bowman’s Layer: Collagen layer that supports corneal shape. 3. Stroma: Thickest layer; made of water and proteins, it helps your eyes to focus. 4. Dua’s Layer: Thin, recently discovered; function unknown. 5. Descemet’s Membrane: Strong layer protecting against infection and injury. 6. Endothelium: Inner layer; pumps out excess fluid to keep the cornea clear. LENS The lens of the eye, also called the crystalline lens, it allows the eye to focus on objects at varying distances. It sits behind the iris and in front of the vitreous body. Naturally shaped like an ellipsoid, it measures about 10 mm across and 4 mm front-to-back.. RETINA RETINA situated behind the iris and lens light-sensitive tissue that converts light into nerve signals and are sent to the brain through the optic nerve it absorbs incoming photons and sends them down neural pathways as chemical and electrical impulses to enable the brain to interpret a visual image RETINAL BLOOD VESSELS The retina is supplied by two vascular systems: The central retinal artery - supplies the inner retina The choriocapillaris - supplies the retinal pigment epithelium and outer retina Retinal Pigment Epithelium (RPE) is a single layer of cells tightly joined so that they form a barrier between the retina and the underlying choroid HYALOID CANAL In the fetus, the hyaloid canal contains a prolongation of the central artery of the retina and the hyaloid retina, which supplies blood to the developing lens. Once the lens is fully developed the hyaloid artery retracts and the hyaloid canal contains lymph. The hyaloid canal appears to have no function in the adult eye, though its remnant structure can be seen. HYALOID artery Usually fully regressed before birth, its purpose is to supply nutrients to the developing lens in the growing fetus. More commonly, small remnants of the artery may remain. Free remnants can sometimes be seen as "floaters" OPTIC NERVE It is comprised of millions of nerve fibers that send visual messages to your brain to help you see. It is a purely sensory nerve that conveys visual information from the eye to the brain. VITREOUS BODY The vitreous body is the clear gel (body fluid) that fills the space between the lens and the retina of the eyeball (the vitreous chamber). This helps to maintain the shape of retina. COMMON DISORDERS OF THE HUMAN EYE AMD Age-related Macular Degeneration is the blurring of the central vision. Wherein the macula, a part of the retina that controls sharp, straight- ahead vision gets damaged due to old age. amblyopia Commonly known as Lazy Eye, wherein there is poor vision in one eye. This due to the fact that the brain does not recognize the sight from the one eye. Over time, as the brain relies more on the stronger eye, the other gets weaker and worse. Astigmatism Astigmatism is a common eye problem that can make your vision blurry or distorted. Astigmatism happens when your cornea or lens has a different shape than normal. Astigmatism Color Blindness You perceive colors differently than most people if you have color blindness, also known as color vision deficit. The most prevalent kind of color vision impairment makes it difficult to distinguish between red and green. Color Blindness Yellow and blue appear the same in another type. A uncommon condition known as total color vision deficit occurs when a person is completely incapable of seeing color. Diabetic retinopathy Diabetic retinopathy is an eye disease that can lead to blindness and visual loss due to diabetics. The retina, the light-sensitive layer of tissue in the rear of your eye, has blood vessels affected. Diabetic retinopathy glaucoma Glaucoma is a group of eye diseases that can cause vision loss and blindness by damaging a nerve in the back of your eye called the optic nerve. Cataracts A cataract is a cloudy area in the lens of your eye (the clear part of the eye that helps to focus light). over time, cataracts can make your vision blurry, hazy, or less colorful. how to take care of the human eye 1. Maintain a healthy diet: Nutrients like vitamins A, C, and E support eye health. 2. Practice regular eye exams: Detects early signs of eye conditions for timely treatment. 3. Protective eyewear: Shields your eyes from injury or harmful rays during activities like sports or sun exposure. 4. Proper sleep: Allows eyes to rest and recover from daily strain. 5. Hand hygiene: Prevents infections from touching your eyes.  FOLLOW THE 20-20-20 RULE Take a break from using digital screens for every 20 minutes, During this time, concecrate on any object 20 feet away from you. Blink your eyes at least 20 times this help avoid dryness in the eyes. Every 20 minutes, leave your seat and walk 202 steps  any QUESTIONS? if none, thank you for listening