-Benjamin
Sunday, March 9, 2008
Saturday, March 8, 2008
For the benefit of Glaucoma patients, like my uncle, I would like to share a little more information about intraocular pressure ( pressure in our eyes) which is one of the causes of glaucoma.
Glaucoma is caused by either
1) increased intraocular pressure or
cause compression of the optic nerve or reduced blood supply to optic nerve
2) vascular abnormalities
cause lack of blood flow to the optic nerve.
Increased intraocular pressure results from fluid build up in our eyes. The circulation of this fluid inside the front part our eyes (anterior chamber) is to nourish structures and wash away toxins. The fluid is constantly being produced and drained. There may be cases where the fluid drainage pathway located in the anterior chamber angle malfunctions or becomes blocked, while fluid production continues as usual. This is when the build-up of fluid occurs.
I would like to end off by saying that this blog has been of a great help to me and I believe that it will be a great source of help and comfort to those in need. May everyone excercise good eye care habits and treasure our gift of sight. Remember, prevention is better than cure.
Glaucoma is caused by either
1) increased intraocular pressure or
cause compression of the optic nerve or reduced blood supply to optic nerve
2) vascular abnormalities
cause lack of blood flow to the optic nerve.
Increased intraocular pressure results from fluid build up in our eyes. The circulation of this fluid inside the front part our eyes (anterior chamber) is to nourish structures and wash away toxins. The fluid is constantly being produced and drained. There may be cases where the fluid drainage pathway located in the anterior chamber angle malfunctions or becomes blocked, while fluid production continues as usual. This is when the build-up of fluid occurs.I would like to end off by saying that this blog has been of a great help to me and I believe that it will be a great source of help and comfort to those in need. May everyone excercise good eye care habits and treasure our gift of sight. Remember, prevention is better than cure.
~nuggets
After reading the previous posts, i was compelled to further research about the eye, and indeed, i have managed to find out more about the specific and specialised structures and functions of the eye.
Below are some of them,
A more indepth analysis about the retina:
The retina is a 5 square centimeter area in the back of the eye, where all light detection takes place. It consists of over 100 million photo-sensitive rods and cones. The signals created by these rods and cones are then sent via the optic nerve to the brain. The brain then processes these and interprets the message, allowing us to see images.
Rods and Cones react to different levels of light. Cones are photopic, which means that they respond to high light levels. Rods are scotopic, which means they respond to low levels of light. Depending on the amount of light striking the retina, one kind of cell will become more responsive, while the other will "turn off." The human eye has about 7 million cones and 120 million rods. Nocturnal animals, such as cats, have more rods and fewer cones. Many diurnal animals, such as pigeons, only have cones.
Focusing or Accomodation:
Light entering the eye is focused by two lenses: the cornea and the eye lens. The lenses hold their shape due to pressure from the vitreous humor and aqueous humor, as well as a muscle group called the ciliary muscles. Light is refracted by the lenses to focus at the back of the eye. As objects get further away from the eye the ciliary muscles relax, allowing the eye lens to become flatter and bend the light differently. Sometimes, due to age or genetics, the ciliary muscles will not bend the eye lens correctly, causing a blurred image. This condition is called either myopia (nearsightedness) or hyperopia (farsightedness).
Light control:
The iris changes in size to allow different amounts of light to enter your eye.When there is more light, the iris shrinks. This is done by the contraction of the circular muscles and the relaxation of the radial muscles. This blocks out much of the light,and as is demonstrated by the first activity, thisincreases the sharpness of your vision. If there is less light, the circular muscles relax and the radial muscles contract. The iris increases in size, allowing more light to enter the eye to be processed.
Below are some of them,
A more indepth analysis about the retina:
The retina is a 5 square centimeter area in the back of the eye, where all light detection takes place. It consists of over 100 million photo-sensitive rods and cones. The signals created by these rods and cones are then sent via the optic nerve to the brain. The brain then processes these and interprets the message, allowing us to see images.
Rods and Cones react to different levels of light. Cones are photopic, which means that they respond to high light levels. Rods are scotopic, which means they respond to low levels of light. Depending on the amount of light striking the retina, one kind of cell will become more responsive, while the other will "turn off." The human eye has about 7 million cones and 120 million rods. Nocturnal animals, such as cats, have more rods and fewer cones. Many diurnal animals, such as pigeons, only have cones. Focusing or Accomodation:
Light entering the eye is focused by two lenses: the cornea and the eye lens. The lenses hold their shape due to pressure from the vitreous humor and aqueous humor, as well as a muscle group called the ciliary muscles. Light is refracted by the lenses to focus at the back of the eye. As objects get further away from the eye the ciliary muscles relax, allowing the eye lens to become flatter and bend the light differently. Sometimes, due to age or genetics, the ciliary muscles will not bend the eye lens correctly, causing a blurred image. This condition is called either myopia (nearsightedness) or hyperopia (farsightedness).
Light control:The iris changes in size to allow different amounts of light to enter your eye.When there is more light, the iris shrinks. This is done by the contraction of the circular muscles and the relaxation of the radial muscles. This blocks out much of the light,and as is demonstrated by the first activity, thisincreases the sharpness of your vision. If there is less light, the circular muscles relax and the radial muscles contract. The iris increases in size, allowing more light to enter the eye to be processed.
If you are still keen to find out more, here's a good website which provides fun activities to test out the different functions of the eye. Go to (http://library.thinkquest.org/27066/theeye/nlstructure.html), and try the experiments out. I hope you all would enjoy them =)
-Benjamin
Thanks to Doctor Alexandra, I feel relieved to know that there actually are treatments that can help us cure from these eye diseases but prevention is better than cure. Now that I have the knowledge of the preventive measures that will help us to lower the risks of contacting the different eye illnesses, I will take note of the little habits that can help me maintain a healthy lifestyle. We should eat more fruits and vegetables as they are often linked with a decreased incidence of macular degeneration. Using the right glasses will optimize your vision. Regular eye examinations ensure that our eyeglass prescription is correct.I heeded Doctor Alexandra’s advice and have recently consulted an eye specialist, Ophthalmologist for an eye checkup. I will remember to go for an eye examination regularly. After reading this blog, I also learned more about the symptoms of the eye diseases that will occur. Regconising these symptoms like sudden loss of vision in one eye, sudden hazy or blurred vision, flashes of light, black spots, or halos or rainbows around lights will let me know that they may signal a serious medical problem, such as acute glaucoma, a stroke, or some other treatable retinal condition such as retinal tear or detachment. I will then be able to do the correct actions by seeking immediate medical care.
Diabetes and high blood pressure are often a cause for the eye diseases. One resultant illness from diabetes is Diabetic Retinopathy. Diabetes causes abnormal changes in the blood vessels throughout the body, including the retina. The blood vessels may grow in places where they should not be and sometimes hemorrhage in the eye, tainting the normally clear humor. Even if a person is suffering form diabetes, he or she should be able to avoid contacting this disease be controlling their blood level and have regular eye checks. An NIH study showed that better control of blood sugar levels will slow the onset and progression of retinopathy and therefore will lessen the need for laser surgery. As the symptoms of these diseases are often ignored, regular checks will allow doctors and patients to detect and treat the problems early, saving their sight.
-Donald
Friday, March 7, 2008
I agree with you benjamin. Our eyes are one of the most important organs in our bodies. It is horrifying to know that that there are such eye diseases that can actually cause blindness. The loss of sight is a terrible loss. The Blind live in a world of darkness. Unlike you and me, they will never get to experience the colours in our lives, they are unable to understand or marvel at the wonders of nature.
Millions of people out there are struggling with the loss of sight. Three of the most common diseases which cause blindness are, cataracts, Trachoma, and glaucoma, which is the disease my uncle is suffering from.
Millions of people out there are struggling with the loss of sight. Three of the most common diseases which cause blindness are, cataracts, Trachoma, and glaucoma, which is the disease my uncle is suffering from.
cataracts, trachoma, glaucoma
Cataracts, as Doctor Alexandra has elaborated in her earlier post, is when your lenses become clouded/opaque, thus impairing one's vision. Trachoma is caused by a virus that affects the cornea and the conjunctiva (lining of the eyelid) Unfortunately, it is contagious and can be spread by flies and contact with articles that have been used by carriers of the disease(e.g through towels). The disease can be cured in the early stages by using medicines.
I feel that it is important for healthy individuals like you and me to treasure this gift of sight. People like my uncle, are considered lucky enough to have contracted eye disease and yet escaped total blindness. Fortunately for my uncle, he was able to keep some of his vision, like majority of glaucoma sufferers. (only a small percentage of glaucoma sufferers become completely blind)
~ nuggets
oh.. I do symphatise with how you both feel, Nuggets and Donald. It may be painful to learn or come to know that either your loved ones, or you yourself has contracted an eye disease. However, contracting an eye disease is not everything, you still have to get on with life.
Agreeing with what Dr Alexandra has said, that a person is prone to eye diseases, and to some there are cures, to some there are not. In addition, i learnt from my biology teacher that vitamins and minerals might affect age-related eye conditions such as age-related macular-degeneration (AMD) and cataracts.
Good nutrition is important to one's eye, other than health. An eye condition called ‘xerophthalmia’, which is a common cause of childhood blindness in developing countries, is a good example of how nutrition and eye health go hand in hand. This condition is caused by a lack of vitamin A in a person’s diet and could be prevented. A balanced diet, with plenty of fresh fruits and vegetables is good for your eye health. Eating a diet low in saturated fats but rich in omega 3 fats and micronutrients derived from green leafy vegetables, fruit, fish and nuts may help prevent and slow down the progression of AMD and age-related cataracts.
I hope what I have learnt would aid you guys as well =), and that we all should take good care of our eyes, as they are one of the most important organs present in our bodies.
Agreeing with what Dr Alexandra has said, that a person is prone to eye diseases, and to some there are cures, to some there are not. In addition, i learnt from my biology teacher that vitamins and minerals might affect age-related eye conditions such as age-related macular-degeneration (AMD) and cataracts.
Good nutrition is important to one's eye, other than health. An eye condition called ‘xerophthalmia’, which is a common cause of childhood blindness in developing countries, is a good example of how nutrition and eye health go hand in hand. This condition is caused by a lack of vitamin A in a person’s diet and could be prevented. A balanced diet, with plenty of fresh fruits and vegetables is good for your eye health. Eating a diet low in saturated fats but rich in omega 3 fats and micronutrients derived from green leafy vegetables, fruit, fish and nuts may help prevent and slow down the progression of AMD and age-related cataracts.
I hope what I have learnt would aid you guys as well =), and that we all should take good care of our eyes, as they are one of the most important organs present in our bodies.
-Benjamin
Thank you Doctor Alexandra, for raising my awareness on my uncle's disease, specifically, angle closure glaucoma. I am relieved to know that although there is no cure for glaucoma, the disease can be kept in control by lowering Intraocular pressure of the eye via using one or more eye drops, oral medications, laser treatment, surgery or a combination of the different types of treatment.
~nuggets
Thursday, March 6, 2008
Secondly, regarding the questions directed by Donald, as an individual ages, he or she does get prone to more eye diseases, namely cataracts, farsightedness and age related macular degeneration.
Farsightedness is the defect of vision caused by an imperfection in the eye, causing an inability to focus on near objects, but in extreme cases, they might even lose the ability to focus on objects of any distance. Patients suffering from farsightedness can experience blurred vision, accomodative dysfunction and binocular dysfunction. What these patients can do is to visit the optician and get a pair of glasses made with more convex lenses.
A cataract is an opacity that develop in the lens of the eye. It may cause near sightedness, the gradual yellowing and opacification of the lens. Cataracts may be developed due to a few reasons, and one of them because of the long-term exposure to ultraviolet rays. Another cause may be because of diabetes, hypertension and old age. Family history will also play a role in one's chance of getting cataracts.
Macular degeneration is a medical condition found in the elderly in which the centre of the inner lining of the eye, which is the macula area of the retina, suffers thinning and may bleed in serious cases. Symptoms of such diseases include the blurring of vision, shadows and missing area from vision and trouble differentiating colours. Treating such disease may include using optical coherence tomography.
Donald, you do not have to be too worried about these diseases. Just keep a healthy lifestyle and do frequent eye exercises will help to reduce your risk of getting such eye diseases.
Farsightedness is the defect of vision caused by an imperfection in the eye, causing an inability to focus on near objects, but in extreme cases, they might even lose the ability to focus on objects of any distance. Patients suffering from farsightedness can experience blurred vision, accomodative dysfunction and binocular dysfunction. What these patients can do is to visit the optician and get a pair of glasses made with more convex lenses.
A cataract is an opacity that develop in the lens of the eye. It may cause near sightedness, the gradual yellowing and opacification of the lens. Cataracts may be developed due to a few reasons, and one of them because of the long-term exposure to ultraviolet rays. Another cause may be because of diabetes, hypertension and old age. Family history will also play a role in one's chance of getting cataracts.
Macular degeneration is a medical condition found in the elderly in which the centre of the inner lining of the eye, which is the macula area of the retina, suffers thinning and may bleed in serious cases. Symptoms of such diseases include the blurring of vision, shadows and missing area from vision and trouble differentiating colours. Treating such disease may include using optical coherence tomography.
Donald, you do not have to be too worried about these diseases. Just keep a healthy lifestyle and do frequent eye exercises will help to reduce your risk of getting such eye diseases.
-Dr Alexandra Yeo
I have read through the posts which both Nuggets and Donald have written, and I have the answers to them.
Firstly, regarding about the issue Nuggets mentioned about her uncle. Yes, you are right to say that the condition your uncle is suffering from, but do you actually know what it is? Acute angle closure glaucoma is an eye disease in which the internal eye pressure in the eyes increase till it damages the nerve fibres in the optic nerves and cause vision loss. The increase in pressure may be due to the blocked or clogged passages that normally allow fluids to flow into your eye. The block takes place at the angle of the anterior chamber formed by the junction of the cornea and the iris. This disease tends to affect people born with a narrow angle. Acute angle-closure glaucoma is an emergency because optic nerve damage and vision loss can occur within hours of the onset of the problem.
When the pupil dilates, the iris will retract and thicken and it will block a canal which drains the fluids away from the eye. This pressure will damage the optic nerve which may lead to blindness. The symptoms of this disease is like what Nuggets have mentioned, which includes a throbbing headache, redness in the eye, eye pain and blurred vision. However, there may be some people will experience nausea and vomitting.
Nuggets, you do not have to worry too much about your uncle's condition. Medication can be administered to lower the pressure of the eye. Glaucoma eye drops may be applied and your uncle may have to go through surgery to reduce the intraocular pressure. So, your uncle's condition can be kept under control and not face any huge risk. You really do not have to worry that much, do try to remain happy and do not be too bothered about your uncle's condition as his condition is not fatal. =)
Firstly, regarding about the issue Nuggets mentioned about her uncle. Yes, you are right to say that the condition your uncle is suffering from, but do you actually know what it is? Acute angle closure glaucoma is an eye disease in which the internal eye pressure in the eyes increase till it damages the nerve fibres in the optic nerves and cause vision loss. The increase in pressure may be due to the blocked or clogged passages that normally allow fluids to flow into your eye. The block takes place at the angle of the anterior chamber formed by the junction of the cornea and the iris. This disease tends to affect people born with a narrow angle. Acute angle-closure glaucoma is an emergency because optic nerve damage and vision loss can occur within hours of the onset of the problem.
When the pupil dilates, the iris will retract and thicken and it will block a canal which drains the fluids away from the eye. This pressure will damage the optic nerve which may lead to blindness. The symptoms of this disease is like what Nuggets have mentioned, which includes a throbbing headache, redness in the eye, eye pain and blurred vision. However, there may be some people will experience nausea and vomitting.
Nuggets, you do not have to worry too much about your uncle's condition. Medication can be administered to lower the pressure of the eye. Glaucoma eye drops may be applied and your uncle may have to go through surgery to reduce the intraocular pressure. So, your uncle's condition can be kept under control and not face any huge risk. You really do not have to worry that much, do try to remain happy and do not be too bothered about your uncle's condition as his condition is not fatal. =)
-Dr Alexandra Yeo
Wednesday, March 5, 2008
Sigh, once you are old, every illness comes looking for you. Near objects are blurry to me and I often have to squint my eyes to see. Now whenever I need to read things, I have to put on my glasses. Prolonged usages of my eye will also strains my eyes and causes eyestrain and headaches. Other than wearing glasses, I heard that there are surgeries that can treat farsightedness. Can Doctor Alexandra introduce to us about the surgeries that can be used to treat farsightedness?
As an elderly, a lot of diseases may happen. Some diseases will cause a loss of vision. It is a terrifying to have your vision lost suddenly. I heard about another disease that comes with old age too- cataracts. It sounds like a horrible disease. May I know more about it?
-Donald
Hi, I'm nuggets and i'm 12 this year. I came across this blog and thought it would be interesting to share with all of you the importance of our eyes. My uncle is curently suffering from eye disease, a condition ( i heard from the doctor) known as glaucoma.
When I first knew about my uncle's condition, it was a great shock to me as my uncle showed no visible symptoms except just on the day before he was diagnosed.
It started off with a throbbing headache on his left side, which he dismissed lightly. Around 2 hours later, he complained of sudden blurred vision, and eye pain. His eye looked red and sore. The events were so sudden that all of us in the family were taken aback. He was warded into hospital the next day.
The doctor told us more about glaucoma and we learnt that glaucoma is the result of our optic nerve being damaged over a long period of time, causing gradual visual loss. Usually patients don’t notice it until they have already lost quite a lot of their peripheral vision. It is only in the very late stage of the disease that central vision becomes blurred.
These photos show progressive optic nerve damage (indicated by the cup to disc ratio) caused by glaucoma. Notice the pale appearance of the nerve with the 0.9 cup as compared to the nerve with the 0.3 cup.
When I first knew about my uncle's condition, it was a great shock to me as my uncle showed no visible symptoms except just on the day before he was diagnosed.
It started off with a throbbing headache on his left side, which he dismissed lightly. Around 2 hours later, he complained of sudden blurred vision, and eye pain. His eye looked red and sore. The events were so sudden that all of us in the family were taken aback. He was warded into hospital the next day.
The doctor told us more about glaucoma and we learnt that glaucoma is the result of our optic nerve being damaged over a long period of time, causing gradual visual loss. Usually patients don’t notice it until they have already lost quite a lot of their peripheral vision. It is only in the very late stage of the disease that central vision becomes blurred.
These photos show progressive optic nerve damage (indicated by the cup to disc ratio) caused by glaucoma. Notice the pale appearance of the nerve with the 0.9 cup as compared to the nerve with the 0.3 cup.
~ nuggets
Tuesday, March 4, 2008
Hello Benjamin.
What you have learnt in school is correct, I'm glad your teacher is doing such a good job in teaching you all. I'm sure you can be a great doctor in the future.
Firstly, let me tell you about the external structures of the eye:
-Cornea. It is a dome-shaped transparent layer continuous with the sclera. it is a specialised form of the conjunctiva which refracts light rays into the eye.
-Conjunctiva. It is a thransparent membrane covering the sclera and is continuous with the eylids. It will secrete mucus to keep the front of the eyeball moist.
-Iris. It is a circular sheet of muscles which consist both the radial and circular muscles. This is the part of the eye which gives your eye the colour.
-Pupil. It is a hole in the centre of the iris which allows light to enter the eye.
-Eyelids. it protects the cornea from mechanical damage and it will remain partly close to prevent excessive light from entering the eye and damage the light-sensitive tissues.
-Eyelashes. They shield the eye from dust particles.
-Tear gland. It helps to wash away dust particles and keep the cornea moist for oxygen to dissolve in. It also helps to lubricate the conjunctiva to reduce friction when eyelids move.
Next, let me tell you about the internal structures of the eye:
-Sclera. It is a tough, white outer covering of the eyeball that you see when you look into the mirror. It is continuous with the cornea and its function is to protect the eyeball from mechanical damage.
-Choroid. It is the middle layer of the eyeball between the sclera and retina which is pigmented black to prevent internal reflection of light. It contains blood vessels that bring oxygen and nutrients to the eyeball and remove metabolic waste products.
-Ciliary body. It is a thickened region at the front end of the choroid which contains ciliary muscles which controls the thickness of the lens.
-Lens. it is a transparent, circular and biconvex structure which is elastic and changes its shape or thickness in order to refract light onto the retina.
-Suspensory ligament. It is a tissue that is attached to the edge of the lens to the ciliary body.
-Aqueous chamber. It refers to the space between the lens and cornea which is filled with aqueous humour, a transparent, watery fluid which keeps the front of the eyeball firm and helps to refract light into the pupil.
-Vitreous chamber. It is the space behind the lens and it is filled with vitreous humour, a transparent, jelly-like substance which keeps the eyeball firm and helps to refract light onto the retina.
-Retina. This is the innermost layer of the eyeball. It is the light-sensitive layer on which images are formed. It contains light-sensitive cells/photoreceptors which consists of rods and cones.
-Yellow spot. It is a small, yellow depression in the retina directly nehind the lens where images are normally focused.
-Optic nerve. This is the nerve that transmits nerve impulses to the brain when photoreceptors are stimulated.
-Blind spot. It is the region where the optic nerve leaves the eye and it does not contain any rods or cones.
These are the internal and external structures of the eye. I hope these information will help you during your journey of learning Benjamin. Good luck! =)
What you have learnt in school is correct, I'm glad your teacher is doing such a good job in teaching you all. I'm sure you can be a great doctor in the future.
Firstly, let me tell you about the external structures of the eye:-Cornea. It is a dome-shaped transparent layer continuous with the sclera. it is a specialised form of the conjunctiva which refracts light rays into the eye.
-Conjunctiva. It is a thransparent membrane covering the sclera and is continuous with the eylids. It will secrete mucus to keep the front of the eyeball moist.
-Iris. It is a circular sheet of muscles which consist both the radial and circular muscles. This is the part of the eye which gives your eye the colour.
-Pupil. It is a hole in the centre of the iris which allows light to enter the eye.
-Eyelids. it protects the cornea from mechanical damage and it will remain partly close to prevent excessive light from entering the eye and damage the light-sensitive tissues.
-Eyelashes. They shield the eye from dust particles.
-Tear gland. It helps to wash away dust particles and keep the cornea moist for oxygen to dissolve in. It also helps to lubricate the conjunctiva to reduce friction when eyelids move.
Next, let me tell you about the internal structures of the eye:
-Sclera. It is a tough, white outer covering of the eyeball that you see when you look into the mirror. It is continuous with the cornea and its function is to protect the eyeball from mechanical damage.
-Choroid. It is the middle layer of the eyeball between the sclera and retina which is pigmented black to prevent internal reflection of light. It contains blood vessels that bring oxygen and nutrients to the eyeball and remove metabolic waste products.
-Ciliary body. It is a thickened region at the front end of the choroid which contains ciliary muscles which controls the thickness of the lens.
-Lens. it is a transparent, circular and biconvex structure which is elastic and changes its shape or thickness in order to refract light onto the retina.
-Suspensory ligament. It is a tissue that is attached to the edge of the lens to the ciliary body.
-Aqueous chamber. It refers to the space between the lens and cornea which is filled with aqueous humour, a transparent, watery fluid which keeps the front of the eyeball firm and helps to refract light into the pupil.
-Vitreous chamber. It is the space behind the lens and it is filled with vitreous humour, a transparent, jelly-like substance which keeps the eyeball firm and helps to refract light onto the retina.
-Retina. This is the innermost layer of the eyeball. It is the light-sensitive layer on which images are formed. It contains light-sensitive cells/photoreceptors which consists of rods and cones.
-Yellow spot. It is a small, yellow depression in the retina directly nehind the lens where images are normally focused.
-Optic nerve. This is the nerve that transmits nerve impulses to the brain when photoreceptors are stimulated.
-Blind spot. It is the region where the optic nerve leaves the eye and it does not contain any rods or cones.
These are the internal and external structures of the eye. I hope these information will help you during your journey of learning Benjamin. Good luck! =)
-Dr Alexandra Yeo
To further my understanding to the eye, i have invited 3 people to write in this blog.
1. Nuggets - whom is a relative of a blind
2. Donald - an elderly who is worried about the functions of his eyes, and to what diseases would his eye be prone to.
3. Dr Alexandra Yeo - an eye specialist committed to her field.
With the shared expriences and knowledge of these people, hopefully then, i will be able to fully understand the conceptual knowledge about the eye.
So, Dr Alexandra, what are we to know about the eye that we do not know?
1. Nuggets - whom is a relative of a blind
2. Donald - an elderly who is worried about the functions of his eyes, and to what diseases would his eye be prone to.
3. Dr Alexandra Yeo - an eye specialist committed to her field.
With the shared expriences and knowledge of these people, hopefully then, i will be able to fully understand the conceptual knowledge about the eye.
So, Dr Alexandra, what are we to know about the eye that we do not know?
-Benjamin
Monday, March 3, 2008
A very basic thought to note about the eye,
Like any other organism, we all have eyes. The eye is an important organ that detect light, made up of different tissues and light sensitive organs. It is the sense organ responsible for sight.
The simplest eyes do nothing but detect whether the surroundings are light or dark, which is sufficient for vision of the surroundings. However more complex eyes can distinguish shapes and colours. The visual fields of such complex eyes largely overlap, to allow better depth perception (binocular vision), as in humans like you and me; while the eyes of other organisms are placed so as to minimize the overlap, e.g. in rabbits or chameleons.
With more information, you can go to this website which i found to be quite of use.(www.en.wikipedia.org/wiki/Eye)
Like any other organism, we all have eyes. The eye is an important organ that detect light, made up of different tissues and light sensitive organs. It is the sense organ responsible for sight.
The simplest eyes do nothing but detect whether the surroundings are light or dark, which is sufficient for vision of the surroundings. However more complex eyes can distinguish shapes and colours. The visual fields of such complex eyes largely overlap, to allow better depth perception (binocular vision), as in humans like you and me; while the eyes of other organisms are placed so as to minimize the overlap, e.g. in rabbits or chameleons.
With more information, you can go to this website which i found to be quite of use.(www.en.wikipedia.org/wiki/Eye)
-Benjamin
Hi everyone, i am benjamin, a biology student who is currently studying about the eye.Till date, i do not really have an in-depth understanding to it, thus i have set up this blog to increase my understanding of the eye.
Be right back with more information after i have researched about the eye =)
-Benjamin
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