Perfect creature-a human body - The skin senses

Assalam alaikum,all


The Greek philosopher Aristotle believed that all of the senses from the skin were encompassed in the broad category of touch. Today we know that the so-called skin senses include several distinct subsystems, each giving rise to a distinct sensation- including pressure, temperature, and pain. Not surprisingly, some parts of the body have greater skin sensitivity than others- it's especially high in the hands and fingers, the lips and tongue, and the genital areas.
   Among the various senses, the skin senses may be the best example of specificity coding, whereby distinct types of receptors are associated with different sensations. Some of the receptors respond to sustained pressure or very low-frequency vibration. A second type of receptors respond to faster vibrations. Yet another type, called the Ruffini endings, respond to sustained downward pressure or stretching of the skin; among other functions, these latter receptors probably play a key role in helping us monitor and control finger positions.
   Still other receptors are responsible for our sensitivity to temperature-and even here, we encounter specialization. One type of receptor fires whenever the temperature increases in the area immediately surrounding the receptor; a different (and more numerous) type of receptor does the opposite-firing in response to a drop in skin temperature. It turns out that, in most cases, neither of these receptor types is especially active. This is because many mechanisms inside the body work to maintain a constant body temperature, and so neither receptor type is triggered. But if you move close to the radiator or step into cold water, these receptors immediately respond, informing you about these events...

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Color blindness

Assalam Alaikum,all.

Today I share a topic that most of us will thank Allah for this blessing. The most important part-eyes and vision. And the world the way we see it. Not everyone sees the world the same way. For example, not everyone responds to color like most of us do. Some form of color-vision defect is found in 8%  of Caucasian males(but only 0.03% of females; the rate of color blindness is lower in other races). The deficiencies in color vision come in various forms. The great majority of people identified as color blind are actually missing one of the three visual pigments(and so they are "dichromats", not "trichromats"). Other forms of color blindness can involve a defective opponent process or a malfunction in brain circuitry needed for color vision. Most common is a confusion of reds with greens; least common is total color blindness, in which no hues can be distinguished at all. Interestingly, though, most of these problems are rarely noticed in everyday life,and color-blind people can spend many years without even realizing they are color blind. They call stop signs "red" and grass "green" , just like anyone else does. And, presumably, they spend much of their lives believing that others perceive colors the same way they do.
   Color blindness can result from various injuries to the eye or brain, but this condition most commonly has a genetic origin. It is also much more frequent in humans than it is in other primates with color vision similar to our own.
   The perception of color enhances our appreciation of art and, more practically, allows us to distinguish a ripe fruit from a green one. Other aspects of vision are far more important. After all, a color-blind individual can live a perfectly normal life. But the same can't be said for an individual who can't tell a square from a circle, and can't tell whether the shape in front of her is that of an apple or that of a banana. These individuals (known as visual agnosics) are dramatically impaired in their functioning.
Till the next time,
Salam

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Last Judgment - yawm al qiyamah

Assalam alaikum,

Have you ever thought about the judgment day!? No doubt, one day we shall be judged by Allah (swt). Every minor details of our action- good deeds and bad deeds- will get the answer. Before that Great Judgment Day, what if we judge ourselves in this world.

  Hadhrati Shibli, one of scholar of Islam, always kept reminding people around Him saying"Judge yourselves in this world before being judged!". Starting with this sentence in every sermon (waaz) He gave, one day Hadhrati Shibli was asked "In the beginning of every sermon you say 'Judge yourselves before being judged!". "If we judge ourselves in this world, do you think we'll not be judged in hereafter?", the man asked. Hadhrati Shibli's answer was: "Yes, those who live their lives by judging their deeds, may not be judged there. Judgment in this world may be seen enough. Prophet sallallahu alayhi wa sallam said "Hasibi qabla an tuhasabu!",which means, "Bring yourself to account before you are taken to account!".
  Getting the answer, the man made this sentence his life rule and began to live his life purely by judging himself in every action. He performed his prayers with great care. Tried to do his best to avoid the sins. In short, tried not to do the things that he thought he couldn't answer in hereafter. Thus, one night he saw a dream about his master. Hadhrati Shibli was on a white horse towards the sky. The man called Him saying "Wait! Please, wait me, I want to go with you!" The master's answer was like this:" I have been freed from this prison newly, do you think I will wait here!"
  In order to learn the meaning of this dream, he went to his master's house as he woke up. Seeing the funeral, he understood that his master had passed away. He prayed to see his master in his dream. The first question was about his most wondering issue:"You had lived your life by judging yourself, were you freed the judgment there?" The answer was like this:"The Angels came to judge me. We began to talk. At that moment I heard the order from Allah "Don't judge that slave of mine. Because he did his judgment himself in the world. He has come here with pure deeds." After this order the angels disappeared. Hadhrati Shibli told his student:"If you don't want to be taken to account here, don't neglect to judge yourself there. Don't come here with the deeds that you can't give any answer.
   So...Living without thinking of death, without contemplation on committed sins, without judging these sins inside ourselves, how will it work? In that case, one should die before the death comes...the life judgment should be done in this world.......
Salam


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