...to examine a scaled up model of the human eye to understand the image formed in the eye, the optics of accommodation, nearsightedness, and farsightedness. Introduction: The basic structure of the human eye consists of cornea, natural crystalline lens and retina, as shown in Figure 1, in which the lens of the eye does little of the bending of the light rays, most of the refraction is done at the front surface of the cornea and retina plays the role of the film in a camera. Figure 1: Diagram of a human eye Accommodation is the focusing adjustment in which the muscles in the eye change the shape of the crystalline lens to change its focal length. Figure 2: Accommodation by a normal eye a) Lens relaxed, focused at infinity b) Lens thickened, focused on a nearby object Nearsightedness refers to an eye that can focus only on nearby objects. Because the far point is not infinity but some shorter distance, distant objects are not seen clearly. This defect is usually caused by an eyeball that is too long and images of distance objects are focused in front of the retina. In order to correct this defect, a diverging lens should be used as it causes parallel rays to diverge which allowing the rays to be focused at the retina. Figure 3: a) Nearsighted eye b) Nearsighted eye is corrected by use of diverging lens Farsightedness refers to an eye that cannot focus on nearby objects. Although distant objects are usually seen clearly, the near point is somewhat greater...
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...1. What is “special” about the special senses? They are extremely sensitive receptors that supply detailed info about the world. They occupy most of our brain and form the basis for logical and rational decisions 2. What are the 3 types of receptors and what do they do? Photoreceptors, vision Mechanoreceptors, hearing and balance Moreceptors-smell and taste 3. Do perfumes/colognes make you more attractive? (check the box on p. 190) No because humans lack the vomeronasal organ, the organ responsible for detecting pheromones 4. What is sensory adaptation? Getting used to an unchanging sight, smell, or taste 5. Name and briefly describe the two chemical senses. Olfaction-sense of smell Gustation- Sense of taste 6. Why are the senses in 6 referred to as chemical senses? 7. Where are the receptors for taste? In 10,000 tastebuds most of which are on the tongue in small bumps called papillae 8. What are the five categories of taste? Sweet, sour, salty, bitter, umami 9. What is the role of the uvula in taste sensation? When the uvula is open, you can smell the food with the olfactory epithelium. 10. What are the three functional parts of the ear? The outer, middle and inner 11. Briefly describe how hearing works using the proper anatomical terms. When they tympanic membrane vibrates in response to soundwaves, the auditory ossicles move, pulling the stapes in and out where it is connected to the oval window, this...
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...nearsightedness, is a common type of refractive error where close objects appear clearly, but distant objects appear blurry. Myopia develops in eyes that focus images in front of the retina instead of on the retina, which results in blurred vision. This occurs when the eyeball becomes too long and prevents incoming light from focusing directly on the retina. It may also be caused by an abnormal shape of the cornea or lens. Myopia can affect both children and adults. Some of the signs and symptoms of myopia include: * Headaches * Eyestrain * Squinting * Difficulty seeing distant objects, such as highway signs Myopia can be corrected with eyeglasses and contact lenses and surgery. 2. Hyperopia/farsightedness: Hyperopia, also known as farsightedness, is a common type of refractive error where distant objects may be seen more clearly than objects that are near. Hyperopia develops in eyes that focus images behind the retina instead of on the retina, which can result in blurred vision. This occurs when the eyeball is too short, which prevents incoming light from focusing directly on the retina. It may also be caused by an abnormal shape of the cornea or lens. Hyperopia can affect both children and adults. The symptoms of hyperopia vary from person to person. But some common signs and symptoms of hyperopia are very similar to Myopia which are: * Headaches * Eyestrain * Squinting * Blurry vision, especially for close objects 3. Astigmatism: ...
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...HISTORY OF THE CORRECTIVE LENS And how they correct vision 11/16/2012 We generally take for granted one of the world’s most important inventions – spectacles. Imagine what life would be like not being able to see images clearly or sharply. The early history of image magnification is shrouded with mystery. In ancient times, someone noticed that convex-shaped glass magnified images. Around the year 1000 A.D. crude technology began to develop reading stones which were nothing more than simple magnifiers. English Franciscan Friar Roger Bacon discovered that letters could be seen better and larger when viewed through less than half a sphere of glass. Bacon's experiments confirmed the principle of the converging lens. Bacon recognized that this could assist weak eyes or the vision of aged persons. Early recorded evidence demonstrates that glasses first appeared in Pisa, Italy about the year 1286. Each crude lens or crystal was surrounded by a frame and given a handle. They were worn on the face like glasses you see today but held in front of the eyes while reading. Essentially someone took two existing mounted stones and connected them with a rivet. Benjamin Franklin in the 1780's developed the bifocal. Later he wrote, "I therefore had formerly two pairs of spectacles, which I shifted occasionally, as in traveling I sometimes read, and often wanted to regard the prospects. Finding this change troublesome, and not always sufficiently ready...
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...Have you ever wondered about how your eye works or how your eye deteriorates? Imagine not being able to see, or your vision becoming gradually worst, 60% of people suffer from optic eye problems such as farsightedness and colorblindness. There are many reasons for these problems, but there are also cures. To start it off let me tell you about how the eye sees. “First the light enters the eye and bends when it hits the cornea and travels toward the iris. Ciliary muscles around the iris react to light in the room and cause the iris to open or close around the pupil.” “After light travels to the lens, through the pupil.” “After passing through the lens, the light that initially bounced off the screen reaches the light-sensing rod and cone cells...
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...I believe that Clemson University looks for strong, well-rounded students. I believe I would excel here because I try to be the best that I can be in everything that I do — academics, extracurricular activities, and community service projects. I want to make a difference in the world around me. When I was four years old, I was diagnosed with severe farsightedness and Amblyopia. I was prescribed glasses and told that I would need to wear them all of the time. Looking back, I realize that having access to an optometrist at a young age, following his prescription therapy, and wearing my glasses made a positive change in my eyesight. This is one of the main reasons why I started ICARE: I Care About Renewing Eyesight. ICARE is an organization that...
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...What is a sensory adaptation? Illustrate by giving one example Sensory neurons stop generating action potential despite continued stimulation. An example is if one walks into a house with a strong odor, the scent seems to lessen with time due to sensory adaptation. Differentiate between somatic and visceral sensation. Visceral sensation and somatic sensations arise from which part of the body? (Page 568). Somatic sensation signals from receptors located in the skin, joints, and muscles (outside) and Visceral sensation signals from sensory neurons in the walls of soft internal organs. (inside) What is referred pain? How does it occur? Give one example Referred pain is when the pain misinterprets visceral pain coming as coming from somatic sources such as the skin or joints. An example is when pain is radiates from the chest across the shoulder and down the left arm during a heart attack. Summarize how we perceive a given smell (Fig 33.8, page 570). The inhaled odorant molecules bind to receptor proteins on chemoreceptive sensory neurons in the nasal cavity. This initiates an action potential that travels along the neurons axon to the olfactory bulb in the brain In the olfactory bulb, axons of sensory neurons synapse on interneurons. Interneurons in the olfactory lobe relay signals from sensory neurons to other regions of the brain List the five perceptions of taste. What type of stimuli elicits each of these perceptions of taste? Is it possible to map...
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...Question: What are the reasons behind Apple’s success? Before getting into the reasons behind the success of Apple, let’s first know a bit about the company itself. Apple, Inc. is an electronics and software company based in California, USA. Originally known as Apple Computer, the company is familiar to most people as innovators of the personal computer as it is known today. Apple Computer had introduced many of the now-commonplace features of personal computers, including the GUI, the mouse, the floppy disk drive, and color graphics. Apple Computer's Macintosh line of PC's had brought numerous software and hardware components within reach of the average home consumer, often in a stylish case and with an emphasis on usability. The restructured company, now called simply Apple, designs, markets, and sells not only personal computers but also consumer electronics in the form of portable media players and smart phones. Apple also sells intangible goods in the form of software, music, and video. The Apple Store chain operates over 150 branches worldwide, where the devices and software and sold and serviced. Apple is undoubtedly one profitable company. The firm announced recently that during the fourth quarter (its fiscal first quarter), it generated a whopping $46.33 billion in revenue and a profit of $13.06 billion. The company’s revenue figure nearly doubled the sales it posted in the same period back in 2010, and its profit was more than double the figure in the prior year...
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...The advantages and disadvantages of Joint Family The advantages and disadvantages of living in a Joint Family have been discussed in this article. Hope that you will find it useful. The joint family is gradually becoming a passing phenomenon. It, however, still survives in some rare instances, but even there the forces of decay are creeping in. Advantages of Joint Family The advantages of a joint family are more than one can count. * It is the best pattern of living that is most conducive to the growth. * It is based on a principle of equitable economy. It holds it as a rule of creation that all men are not equal. Naturally it imposes a kind of unwritten discipline that those who are more able economically shall share some of the burden of those who are not. * The joint mess, naturally, runs on an understanding of mutual adjustment. Naturally those who are benefitted by the generosity of others remain obliged and grateful. * Similarly in a big joint family the study groups of boys are formed according to their age matching. Naturally the cousins study together, play together, quarrel together and are even punished together. As a result there grows in them a feeling of camaraderie that is free from any discrimination of one being a full brother or a cousin. * In marriages also the grooms for marriageable girls become a concern for all the elders in the family. Even if a daughter of a junior brother is selected by someone because of her beauty or brilliance...
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...environment they live in. It is possible to change one’s traits for better or for worse through conditioning. 1. Self-confidence A leader needs to have the ability to take risks. This ability comes with confidence in his decisions and himself. As examples, Tommy had a solution to solve the glass display production problem by rejecting Richard suggestion; he had already agreed to buy ReflecShine at 20% below its asset value; he chose Jimmy as general manager to run ReflecShine. Tommy had self-confidence and believes on his decisions to overcome problems. Tommy also has emotional stability during meeting. 2. Cognitive ability This is mental abilities and knowledge. Some cognitive skills are insight into people and situation, farsightedness and conceptual thinking. As examples, Tommy knew that they could not ramp up production in Brazil in to time to deliver and could not outsource to a supplier who could steal their design and methods; Tommy also knew that buying ready supplier in Singapore could solve these two problems and give them time until Japan factory is rebuilt. He was also the best at transforming an adversity into opportunity. 3. Micromanaging It is the act of over-managing, or employing too much detail in delegating a task. As examples, the staffs want Tommy to retire because he is just too hands-on. Micromanaging limits leadership effectiveness. Tommy should learn to keep this tendency for over control under his...
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...Chandragupta ll and Samudragupta India is a country that is filled with culture in its government. The Gupta empire `reigned from 320-600 A.D. The Gupta Empire was one of the largest political and military empires in world history. It is also called the Golden Age. The Gupta empire was called the Golden Age because of how many new inventions happened during this time. There were inventions in science, technology, art and language. Since there was so much change the Gupta rulers called themselves Kings. Even when they called themselves kings they did not claim to be divine or magical. There were two very important rulers of the Gupta Empire. Their names are Samudragupta and Chandragupta ll. In this time known as the Golden Age, there was once...
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...Definition for Leadership: -The ability to inspire confidence and support among the people who are needed to archive organizational goals. Leadership is the partnership between leaders and group members. Its the responsibility of one person. They serve as a leader in a team. ”Leadership is not something you do to people , it’s something you do with them” words by Ken Blanchard about leadership. Leader built relationship in Modern era:- Leaders built relationships with interacting with people electronically.Cisco systems is the best example for this. They communicate with group members through blogging’s, uploading videos, and social networking tools – created by company. In the modern organization, leaders innovate there ideas rather than heroic leaders. There are some difference between leadership and managers such as leadership deals with change, inspiration, motivation, and influences. Whereas the management functions are planning, organizing directing and controlling. The efficient leader also manage with efficient managers. The leader’s activity had 66% possibility to archive positive results .strong leader usually makes a difference. Mintzberg and other researchers identified ten roles for the leadership function of management , that can be classified as ,Figure head, Spokesperson, negotiator, Coach & motivator, Team builder, Team player, Technical problem solver, Entrepreneur, Strategic planner, Executor. The effective followers can assign with self-management...
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...Nearsightedness or myopia is a condition of the eye that makes it difficult to see objects that are far away. Although, possibly this study most likely didn’t consider the factors of our technology of today affecting our vision such as cell phones, computers, and tablets. I could only imagine if they would have, the percentage would just have been a lot higher. In nearsighted people, the eyeball is too long or the cornea has too much curvature, so the light entering the eye is not focused correctly. The retina in the eye has light sensitive part causing the vision to be viewed blurry. This is easily fixed by going to the eye doctor and having your options be told to you along if you’re farsighted as well. Hyperopia, also known as farsightedness, is a common type of refractive error where distant objects may seem clearer than objects that are near. However, people experience hyperopia differently. Some people may not notice any problems with their vision, especially when they are young. For people with significant hyperopia, vision can...
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...Advantages Of The Nuclear Family While discussing about the advantages and disadvantages of nuclear family, the first and foremost point pops up in the mind of a person is privacy of life. 1) Privacy – The couple can get their privacy in their own house in nuclear families whereas you cannot get your privacy in a joint family. People can live their own way and can do whatever they want to. There are no such boundaries set by the elders to follow. ) Financial stability – When we talk about the advantages and disadvantages of the nuclear family, then financial stability is one of the strongest points in the nuclear family. One can be financially strong because of limited expenses. There is less number of people in the nuclear family and hence less expenses. You cannot have a strong financial stability if you are the only person who is earning in a joint family. 3) Freedom – The elders restricts youngsters not to do certain tasks because they think this is not good for them. But today’s generation is very smart. They know what is good and bad for them and have enough analytical power so they don’t like to restrict themselves. Instead, they want their freedom so that they can do and achieve whatever they want in their life. 4) Ease in moving – When you have a nuclear family, you face fewer problems while shifting from a house. You can manage your things according to you without disturbing the lives of other people. This is one of the major advantages of the nuclear family. 5)...
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...Piggy is clearly a clever boy, but he is a victim too. How does the writer use him in the novel? Piggy from the start of the novel is portrayed as someone the boys can bully and ridicule which makes him a victim. He confides in Ralph that he is sensitive about his appearance (he is overweight) and the fact he has to wear glasses. I don't care what [you] call me so long as . . . [it's not] what they used to call me in school . . . They used to call me Piggy!'"Ralph finds this funny and straightaway betrays his confidence . Yet it is not long before Piggy proves his worth and intelligence when he spots a conch shell lying in the lagoon and suggests Ralph uses it to call all the boys together. He cant use it because of his asthma . He is the first to suggest that they make a list of the boys names, showing his clear thinking and intelligence. Having called the boys together, Ralph decides it is important that they explore the island but dismisses Piggy with the words "'You're no good on a job like this.'" , which embarrasses Piggy and makes feel like an outcast.. When it is suggested that the boys build a signal fire Ralph turned to Piggy and asked "'Have you got any matches?'" Ralph seems to only bother with Piggy when he wants something. Piggy is portrayed by Golding as an insignificant nobody who is only acknowledged when he has his uses. Jack mutes the idea that Piggy’s glasses could be used to light the fire and snatches them off him. He is respected by no one....
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