Category Zoology

What are tranquillizers?

          A tranquillizer is a drug that calms a person’s mind. It is mostly used to reduce tension and anxiety. It does this without putting one to sleep. Unlike a sedative, it does not induce sleep. However, its tranquillizing effect may sometimes put the person to sleep. If given in the right dosages, most depressants and sedatives can act as tranquillizers.

          The first member of the tranquillizer drug family was phenothiazine. This was first synthesized in the 1880s, but its potentiality remained unrecognized for nearly 70 years. In 1950, some French researchers synthesized the first widely-used tranquillizer — chlorpromazine. Chlorpromazine and its allied drugs lower the activity in certain areas of the brain that are concerned with emotions, such as the cortex, thalamus and hypothalamus. They also have a sedative effect. The benzodiazepine drugs produce a lighter tranquillizing effect and include volium and Librium.

          Tranquillizers are being used for many mental illnesses such as schizophrenia and anxiety neuroses. Chlorpromazine has been used especially in the treatment of schizophrenia. 

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What is Extrasensory Perception?

            In our day-to-day life we often come across situations where we get the knowledge of an event before it happens or become aware of something that is out of sight, or can read what another person thinks, etc. This happens without the use of any of the five senses — sight, hearing, smell, taste and touch. Hence we call this ability as Extrasensory Perception (ESP) which literally means ‘awareness outside the senses’. Some people also call it as the ‘sixth sense’. Usually we perceive everything around us with the help of our five senses but ESP provides us with information which are normally not conveyed by any of the five senses.

            But the scientists as well as psychologists are not unanimous about the existence of ESP. The controversy is that this phenomenon can be explained in other ways and science has not been able to either explain or prove this. 

            There are four basic areas of experiments in the field of extrasensory perception. These experiments involved telepathy, clairvoyance, precognition and psychokinesis. The ESP researchers use a special deck of cards. This deck is made up of 25 cards with certain symbols such as a cross, a circle, a star, wavy lines and a square etc. At the Duke University (North Carolina) Professor J.B. Rhine has published a book titled Extrasensory Perception (1934) after carrying on experiments on it for more than three decades.

            In the telepathy experiments, a person tries to ‘read the mind’ of the one conducting the experiment by guessing the cards. Telepathy involves sending of thoughts, feelings or knowledge from one person to another without any apparent medium. It is often called thought transference.

            Clairvoyance is the state of being mentally aware of something that is out of sight such as an event or a person, without the telepathic help from any other person. In the clairvoyance tests, a person identifies cards through various methods without seeing them. When the number of current guesses is higher than the average person achieves, it suggests that the person has extrasensory perception.

            Precognition is the knowledge of an event, by means of telepathy or clairvoyance, before it takes place. In the precognition tests, by using cards or a dice, an attempt is made to predict a sequence of events before they actually occur.

            Psychokinesis is the psychological control of physical objects. For example, while tossing a coin, a person might concentrate on the ‘heads’ and cause it to appear.

            It is said that all the people do not possess such powers to see the truth directly without reasoning. There are many examples of people possessing such abilities and ESP is a convenient way of acknowledging this.

            The scientists have been studying this phenomenon because they feel it has enormous potential for a fruitful research. For example, a person with ESP abilities might be able to predict future wars, locate valuable mineral deposits or even accomplish other things of great importance.  

What are pesticides?

            Any plant or animal that occurs in such abundance as to pose a distinct threat to man or his interests is called a pest. And the chemicals used for mitigation, control or elimination of such plants or animals are known as pesticides. Today we have algaecides, defoliants, herbicides, plant growth regulators and fungicides in use to control the growth of undesirable plants which compete with crops or other useful plants. Attractants, insecticides, miticides or acaricides, molluscicides, nematocides, repellents and rodenticides are used to reduce parasitism and disease-transmitting organisms in animals, crops, plants, foods, textiles and human beings.

            Most of the pesticides are chemical compounds and act in a similar fashion, i.e. by blocking some metabolic process. They, however, differ in composition, potency, mode of action, speed of effect. So different pesticides are used at different stages of infection. 

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Why are crocodiles so dangerous?

          A crocodile is a large reptile with a long cigar-shaped body, short legs and a powerful tail and jaws. They have a heavy body covered with bony scales. Its pointed snout and long partially exposed sharp teeth distinguish it from an alligator (another species of the same family). A crocodile is generally more aggressive than an alligator and may attack large animals such as deer or even human beings. Caymans and Gavials are the largest living reptiles of this family.

          All the crocodiles are carnivores and live in water. Since their eyes and nostrils are located a little higher than the rest of their head, they can hide in water staying almost completely submerged and still able to breath and watch the movement of their prey. They are particularly successful in catching smaller animals because they can float closely up to their prey without being seen. Once they catch their prey they slowly tear it apart in bits by gripping with the teeth and turning it over and over again. The crocodiles have been seen mysteriously more aggressive when protecting a nest or when the water is drying up. They usually feed on fish, birds and small mammals.

          The crocodiles live in tropical areas throughout the world, usually in swamps or marshes, or along slow-moving rivers. They have webbed feet which help them walk on wet or muddy ground. 

How is Nightingale distinct from other birds?

               In the kingdom of birds, nightingale enjoys a unique status for its ability to sing. This quality of nightingale has made it quite popular with poets and no bird has been written of so much by the poets as the nightingale. Aristophanes, the great Greek poet wrote about it in the 4th century B.C. and Keats in the 19th century.

               According to the poets, the nightingale sings only at night  and in almost any season of the year. But this goes against the facts as the bird sings both in the day as well as in the night. Poets had a wrong perception because they could hear it only in the night and not in the day. The reason for this being that the song of nightingale is not audible in the day as it is being overshadowed by the chirping of other birds but it is distinctly heard in the silence of the night. Again, since nightingale is a migratory bird hence its voice is generally not heard throughout the year at a particular place. From season to season, it migrates to different places. 

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How do plants and animals defend themselves?

                    Almost every plant and animal in the world has enemies that threaten its existence. So to protect itself every living being has developed some defence mechanism. Sensing the danger some organisms hide, others run, while others just fly away. 

                 Some organisms can even hide without moving. They use ‘camouflage colouring’. That means that their skin colour blends in with the matching colour of the surrounding area so well that the enemies cannot see them. Chameleon has the capacity of changing its body colours. If it is on a green leaf, it turns green; if on a brown twig, it turns brown. Some rabbits change colour with the season. The snowshoe hare is brown in summer and white in winter. The white fur camouflages the rabbit in the snow. Another phenomenon called counter-shading is a common type of camouflage among the fishes. The underside of their body is of lighter shade than the top. This helps the fish to blend in with many shadows it might make. Some other animals have a remarkable ability to take the form and colour of some other object around them. Camouflage also helps some animals catch their food. Since they can blend in with their surroundings, their victims can’t spot them immediately, and thus get caught.

                    Then there are other animals such as antelope who can run very fast. Others may dodge back and forth, like a rabbit. Birds can escape most predators by flying away. 

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