Our Ears detect Sound

How do the ears detect sound?

We hear a number of sounds every day. Some are pleasant while others are not. On the basis of its structure the human ear can be divided into there parts external, middle and internal. Anything producing sound first vibrates. These vibrations set up a motion of sound waves in the medium through which the sound reaches our ear. The external ear has large surface and can receive a number of sound waves at the same time.

The internal structure of human ear

            When the sound waves hit the external ear, they are transmitted to the middle ear through a pipe. The middle part has the ear drum, which starts vibrating when tenses sound waves hit it. Just behind the ear drum there are three small bones called hummer anvil and stirrup. As the ear drum vibrates, these bones also start vibrating. These vibrating are then transmitted to the cochlea. Which acts like a spring it is surrounded by a fluid the fluid contains the nerve ending.

Due to the vibrations of cochlea the fluid also starts vibrating and this activates the nerve endings. The activation of the nerve ending produce impulse which are taken to the brain the auditory nerve and we hear the sound.

            Our ears can detect both feeble and intense sounds with frequencies ranging from 20 Hz to 20,000 Hz. In the order to keep the ear healthy, it is essential to produced in the ear, which gets deposited on the ear drum if it is not cleaned. If this wax accumulates then it can lead of our ears and consult the ENT expert as soon as there is trouble in the ears.

We Feel Thirsty

Why do we feel thirsty?

            Why do you think we feel more thirsty when we exercise or when we are tense? Many people think that parching of mouth or throat is only caused by thirst. But, this is not true. Such parching can occur due to many other cases also. Tension or production of less saliva by the salivary glands as also produces thirst and so can nervousness. Have you ever wondered why we feel thirsty? Present in our blood. The body tissues also contain these two substances. Under the normal condition, the proportion of these two materials in blood remains constant. If due to some reason, the amount of water in blood gets reduced, the proportion of these two materials in blood remains constant. If due to some reason, the proportion of the two materials also changes. In such a situation, the thirst center located in the brain sends signals to the throat. As a result of this, the throat starts contracting. This contraction makes it dry ad we start feeling thirsty and want to drink water.

We feel thirsty when the amount of water in blood gets reduced

            However, sometimes, the salivary glands secrete enough saliva and our stomach and blood too have enough water and yet we feel thirsty. For example, when man drinks liquor he takes enough quantity of slated preparations along with the drink. Though the amount of water goes on increasing with the intake of liquor, consumption of salted foods also increases the quantity of salt in blood. As a result of this, the amount of salt in blood exceeds the normal level. This disturbs the normal proportion of salt and water in the blood. In such a situation, we feel thirsty. Excessive thirst may be a symptom of diabetes or kidneys ailments. In such cases, immediate medical check up should be undertaken.

One of our Feet Bigger than the Other

Why is one of our feet bigger than the other?

            You may not believe this but our feet differ in size from each other. Have you even measured or compared one of your feet with the other? What did you notice? If we carefully measure our feet we will observe that the right foot is slightly bigger than the left one. Do you know why it is so?

            The structure of our body is not completely symmetrical. There is a little symmetry between the left and right sides of the body. If we notice carefully, we find the right side of our face is slightly more developed than the left side. The length of the right leg is slightly more than that of the left one. The right hand is slightly bigger than the left one. Our heart is located on the left while the liver on the right. The inner constitution of the body is not in complete symmetry. That is why even the development of bones is slightly a symmetrical. Because of this a symmetrical development, our right foot is slightly bigger then the left foot.

Our right side is slightly more developed than the left side

            The asymmetrical structure of the body affects us in many ways. One of the effects of this is that we are not able to walk in a straight line if we are blind folded. We start moving in circles. This is true of animals also.

            Are you curious about why the right side is slightly more developed than the left one? Though nothing can be said with certainty about this, scientist hold the view that since most of the people use their right limbs more often for any work, their right side gets more developed than the left. 96% of the total population of the world uses right hands more than left ones. Only 4% are left handed. The brain controls the use of the right or the left hand. It is the left part of the brain, which regulates the functioning of the right limbs, and the right part of the brain controls the left limbs of the body. In the world, greater number of people has the left side of their brain more developed than the right one. Hence, the number of right hander’s is also large.

What Causes People to Faint?

            We often see that people faint on receiving some tragic news or on getting frightened suddenly. The body gets drenched in sweat and becomes cold. The face turns pale and physical consciousness decreases.

            Unconsciousness is a factor that has puzzled men for a long time.

            Unconsciousness can be caused not only by a shocking new or terrible fear, but by many other factors also. People may faint because of confinement in a closed and poorly ventilated room, hunger, fatigue, severe pain, emotional shock, some heart problem, and sudden fall in blood sugar. Have you wondered why people become unconscious under these conditions?

Treatment to Unconscious Man

            In order to be aware of the reasons of fainting, it is essential to know what consciousness is. For the normal functioning of the brain, it is essential that there should be proper circulation of blood in the brain. As log as the brain gets its proper supply of blood, all our physical activities remain normal. The normal functioning of the brain is, in fact, consciousness. If there is some obstruction in the blood supply to the brain, our physical processes get disturbed. Whatever may be the cause of fainting, man will become unconscious when the normal supply of blood of the brain is disrupted. Hence fainting or syncope is a temporary loss of consciousness resulting form insufficient supply of blood to the brain.

            The following measures can prevent the state of unconsciousness. If somebody feels that he is about to faint, he should immediately lie down. If this is not possible, he should bend downwards and enclose his head in between the knees. Both these measures enhance the blood supply to the brain. As long as the brain receives a proper supply of blood, a person’s chances of becoming unconscious are greatly reduced.

            If somebody has become unconscious, he should be laid down and his clothes should be loosened so that he can breathe easily. His head should be kept at a little lower level than the rest of his body. This will increase the blood supply to his brain and he will regain consciousness. Once he is conscious, he should be given tea or coffee. If somebody has fainted because of head injury or heat stroke, he should be taken to hospital immediately.

What is Memory?

        Different people have different memory spans. Have you ever wondered why some people can remember things that look place five years ago, while others can’t remember an incident that took place a year back? This is due to the difference in memory span.

Human Brain and Functions

            Memory can be defined as the capacity to keep information available for later use. The process of memory can be divided into four aspects- learning, retention, forgetting and retrieval.

            The initial storage of information is called learning keeping the new information available is called retention the loss of old information over a period of time is called forgetting and utilization of stored information is called retrieval.

            According to psychologists there are four kinds of learning. Classical conditioning is the simplest kind of learning. Ivan Pavlov studied it during the early 1900s. He offered a dog food and at the same time rang a bell. The sight of food made the dogs mouth watered. Pavlov called this an unconditioned response because it was not learned. Soon however ringing the bell was enough to cause the dog mouth to water. This was called conditioned response. Classical conditioning is often called respondent learning.

            Another form of learning is called instrumental. Often a person learns to do something as a result of what happens after the person does it.

            Multiple response learning is the third type and it takes place when a skill is learnt. A sequence of simple things must first be learned. Using a typewriter is a kind of multiple response learning. At first a person has person learns to type word by word or phrase by phrase.

            The fourth type of learning is insight learning. It means solving a problem through understanding how the different parts of a problem fit together. A simple example is that of a young child wanting to climb on the top of a table. The child may use a stool to get onto the chair and then use the chair to climb onto the table.

            There are two basic theories to explain the process of memorizing events. According to one theory memory is said to be stored in the bring as a memory trace. When we learn or experience something impulse are generated I the nerves of the brain.

            These impulses impart their effects I the brain in the form of a record. According to the other theory sensations by learning produce some permanent changes in the brain which remain there in the form of memory.

            According to some biologists the RNA present in the brain keeps the record of events. It has been observed that the quantity of RNA present in the brain keeps on increasing from the age of there to the age of forty. During these years the memory of the man also increases.

            The quantity of RNA is almost constant from the age of 40 to 55 or 60. Therefore a mans memory is almost constant during this period. After the age of 60 the quantity of RNA starts decreasing and so does the memory.

             The only effective way of remembering things is to repent them many times. Interest is every important. Boring things are much more difficult to remember than something that we understand and are interested in. motivation or desire to do something is also important.