Why don't women have beard?

    The ways of nature are peculiar. Some living beings have hair on their bodies, while some others have wings on them. Broadly speaking, mammals have hair on their bodies, while birds have wings. Hair preserve the body-heat and protect the body from being burnt by the
scorching heat of the sun. It also helps us in realising the sensation of physiacal touch.
    Now the question is: why do men have beards, and women do not? This can be understood as follows.
    When a child is born, he has only fur like hair on the body. As he grows, hair become harder. Boys and girls reach puberty at the age of 11 to 13 years. There is faster growth of sex glands at this age. In man, the testes or other sex glands, produce a group of sex hormones known as 'androgens'. In woman, the ovaries or other sex glands, produce another group known as 'estrogens'. The function of the androgens is to regulate secondary male sex features such as the growth of facial and chest hair and deepening of the male voice at puberty. The function of the estrogens is to regulate secondary female features, such as the change in the size of breasts at puberty and the menstrual cycle. There are various other changes in men and women broyght about by these hormones. For example female body becomes soft and tender whereas, male body turns hard and strong. A special group of estrogens is called the 'progestrogens'; they are responsible for the regulation of pregnancy. Hence women do not have beards due to the absence of androgens.

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How do we lose our memory?

    Some people lose their memory after some accident or on hearing some tragic news.Such people forget their past and even fail to recognise their close friends and relatives.So much so they even forget their names.In psycholgy this disease is called 'amnesia'.
    Amnesia is caused by many factors.Head injury, metal shock, extreme tiredness, ill-effects of medicines, surgery of brain, phychological processes, old age
and after effects of drinking are some of the reasons which reduce or completrly destory memory.What ever may be the redsons causing amnesia,its effects on brain is almost the same in each case.Memory is said to be the brain as a"memory trace".What makes up this trace is not known. According to one theory each experience sets up an oscillating pattern or wave of electrical excitation in a group of cells. Each learning experience generates its own pattern of excitation. A given neuron may participate in thousands of separate memories but its removal will not diminish any of them.
    Memory is considered a three-part system. Sensory information store (SIS), short-term memory (STM) and long term memory. The SIS forms an instant, but very temporary, storage of every piece of information that come in. Information can last for only about three tenths of a second in the SIS. If it has not been selected and transferred to short-term memory within this time, it fades away.
    Short-term memory is used for carrying information a person needs for a few seconds, but can afford to forget later. Two characteristics of short term memory prevent its use as a permanent information store. First concentration is required to maintain a particular piece of information in it. Second, it is able to store only six or seven items such as a seven digit telephone number.
    For any information to be permanently stored, it has to be passed from short-term to long-term memory by the mechanism of rehearsal.
    The long-term memory has virtually unlimited capacity. It allows a person to remember events that have happened years before. Permanent memory takes place through structural changes in nerve cells, caused by patterns of electrical activity in these cells.
    When somebody suffers from amnesia, he forgets events either preceding it or following it. It can last for weeks, months or for years. There are people who have lost memory for life. When memory is restored, one remembers all the forgotten things but forgets every event which took place during the period when one had lost memory. One thing is however certain that in spite of the restoration of memory, some aftereffects do remain, thereby weakening the memory. In cases involving loss of memory, assistance of psychiatrists should be obtained immediately. Normally old age weakens memory, but sometimes peptic ulcer, high blood pressure, asthma etc. also affect memory.

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Why can't animals talk like us?

    In many stories,it is told that animals can also talk like us.But they do not talk like us.Amongst all the living beings,man is the only creature who can communicate with one another with the help of words.Even though,it is a fact that animals do not talk with one another with help of words.Even though,it is a fact that animals do not talk with one another like us,yet they also express their happiness, sorrow, fear etc.
with the help of certain gestures and sounds. you might have seen that when a cat passea by a group of birds,all the birds start chirping very loudly in apeculiar way. They actually express their fear of being caught by the cat.Similarly,the dog expresses its anger by barking and flattery by wagging its tail.The moneky also demonstrates its anger by making peculiar sounds.
    Do you know why animals cannot talk like us?This is because the brain of animal is less developed in comparison to the human beings.It is a fact that feelings are generated in the animals-but they lack words to bring them out So they are incapable of expressing their feeling in some language.They do it by some gestures and sounds.These feeling clearly bring out their love ,affection,anger,hostility etc .They have their own language of expresssing their hunger,thirst or protective needs.Even through they may not utter a sound,they continue uninterrupted communication between themselves.
    It may be pointed out here than ever today,we do not use language for saying everything.Instead ofsaying 'yes' or 'no' on many occasions,we shake our head or signal with hand to communicate our approval or disapproval.We can conclude that due to lesser development to their brain in comparision to ours, animals have not been able to develop words and language to express their feelings Hence they can't talk like us.

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