Neuron is a basic component of the nervous system. The main purpose of a neuron is to get the entering information, and grounding on that information, transmit a signal to other muscles, neurons and glands. Neurons are contrived in such a way that sent signal reach their destinations via physiologically long distances. It becomes possible due to implementation of nerve impulses, which are also called action potentials. When a nerve impulse gets to the end of neuron, it activates chemical remission. It is also called a neurotransmitter. It travels fast through the short gaps between the cells. It signals the contiguous cells.
Reciprocal actions among neurons may be divided into four main steps. The first one is the process when a neuron gets information from the outer environment or from other neurons. For instance, a neuron in the human brain can receive incoming signal from thousands of other neurons. Secondly, the neuron amalgamates, processes the information from its incoming sources, and identifies either sending it to a target signal. This consolidation occurs in time and space. Referring to time, it is the endurance of the incoming signal and the time between incoming signals. Considering space, it refers to the surface crossed by the neuron. Thirdly, the neuron reproduces the signal longwise the distance at high speed. The length may amount up to a few meters, e.g. whale or giraffe, rating up to a hundred meters per second. Ultimately, the neuron changes the electrical signal to the chemical one and dispatches it to other neurons or to a target either a gland or a muscle.
All in all, the major function performed by neuron is to process the information: receiving, conducting, and transmitting it to other cells. Receiving information becomes possible with the help of synapsis with receptors of sensory organs or other neurons, or directly from the outer source together with special dendrites. Transmission of the information occurs in axons via synapsis.
Breathing is an action of respiration during which the air is inhaled via nose and mouth into lungs as a result of muscles contraction and later it is exhaled in consequence of muscle relaxation. There are two groups of muscles involved in the breathing process: inspiratory and expirotary muscles.
Diaphragm is the one of the most important muscles performing the inspiration. It separates abdominal and thoracic cavities. The diaphragm adheres to the lumbar vertebrae of the spine, as well as to the lower ribs. Intercostal muscles sited between adjoining ribs are known as the muscles of the inspiration. They include the outer layer, and they cant forward and downward. Their contraction brings about strengthening of the rib cage while pulling, lifting and pushing movement. It makes the intercostal muscles an inevitable contribution to these movements.
Some muscles of the neck take part in inspiratory actions. Sternomastoid are fastened to the summit of the sternum, over two ribs, and collarbone at the one hand. At the other hand, they are adhered to the mastoid and cervical vertebrate process. During contraction, they raise the upper part of the chest. The scalene muscles also take part in flexure of the neck.
The muscular corset of the abdominal wall forms the principal muscles of expiration. Resting expiration is a passive action performed by the motion of the rib cage and lungs at the end of inhalation. The compression and strengthening of the abdominal walls begotten by the compression of the abdominal muscles also enable the condition of the diaphragm at the umpact of inhalation. It intensifies spinal fixity and postural regulation. Muscles located in the rib cage are involved in the expiratory process. The contraction makes ribs moving inward and downward. Internal as well as external intercoastal muscles help the trunk bending and flexing.
From the very morning and during the all day human’s brain receives signals that the movements begin, though some of them are automatic or rapid. Immediately muscles start burning energy. This process occurs due to the alteration of nutrients and oxygen into adenosine triphosphate, stored fat and carbohydrates are also burnt.
The heart starts beating faster due to pumping more blood into muscles and other organs. As soon as physical activity starts, nervous system receives signals sent by nerve receptors in muscles, joints and blood vessels. The blood enriches with adrenaline and nonadrenaline. It hastens the heartbeat.
Starting exercises leads to some quick changes in blood vessels. Incited by chemical signals and nerves, arteries of the working muscles get relaxed and widen the walls of the arteries. Compression of the peripheral veins speeds up the blood in central circulation. Arterioles in muscles widen and feed the muscles with the blood. These changes fill the body with the oxygen and other important nutrients. Meanwhile, during physical activities the heart muscle receives more blood as usually, and speeds up the blood flow. It increases during muscles relaxation. It stops during contraction.
Lungs start breathing deeply and rapidly, supplying organs with oxygen. Carbon dioxide withdraws, increasing production of acid and body temperature. Exercises increase the rate of the passed in and out air.
The harder exercise the higher metabolic rate makes body burning more calories.
Sweating is a body thermoregulation. It is the fluid produced by the sweat glands. It is inevitable to maintain the body homeostasis. Moreover it is known as an excretory function of the skin. Sweat cools the body and involves evaporating, e.g. turning the liquid into the gas. The skin becomes cool and the body can maintain the normal temperature. It lasts until the surrounding temperature reduces or the physical activity is halted.
Blood loss, especially the significant one, leads to the organs’ stress. It is a response to a lack of the blood flow to the vital organs. They send signal to enlarge energy preservation. This process causes hemorrhagic shock, which in its turn reduce the tension on the walls of the arteries. It is a three-step process as a physiological response of the body to the blood lost. It is characterized by fast respond to humoral and neural mechanisms, which supply vital organs with the blood full of oxygen and nutrients. Hemorrhage causes gradually evolving water and salt preservation by the kidneys supersedes the plasma lost. Erythropoiesis slowly displaces the outage of the red blood cells. The urgent reply includes a primary diminution in cardiac production. Secondly, it declines the arterial pressure and compensative enlargement in vascular resistance and heart rate.
The electrocardiogram is a way to record little electric waves produced by the heart activity. Normal heart beating is identified by small impulses of electric stream. These impulses spread fast in the heart and force the contraction of the heart muscle. A whole heart muscle does not contract at the same time. If it happened the heart would be unable to pump the blood. For this reason the electric impulse start at the summit of the heart and spreads all over the muscle. Pacemaker cells generate electricity by changing electrical charge from negative to positive, and vice versa.
Electrocardiogram is recorded by the electrocardiographer in millovolts. Electrodes are located on the particular parts of the body through which the waves are registered. They are under control of the ink needs which shows the measures. The paper moves with a settled speed fixing an ink curve. If the electric waves intensify, the needle moves higher on the paper, and vice versa. Electrocardiogram helps to find out the problems with the cardiac system. The impulses in the heart muscles changes and these signals are shown on the paper.
Body mass index is a measurement of squared height to weight proportion of a person. It set a percentage of a body fat. This ratio shows either a person is underweight (under 18.5), normal (18.5 – 25), overweight (25-30), or obese (over 30). BMI is used to prognose health result. Index may be affected by non-genetic as well as genetic factors. It helps to find out health problems. Owing to BMI, doctors can discuss and solve their patients’ weight problems.
Cardiovascular disease is an illness relating to the blood vessels and heart. There is distinguished a systolic and diastolic blood pressure. Systolic blood pressure is the highest level of pressure in the arteries of the heart contraction. The diastolic one is the lowest level of pressure in the arteries between the periods the heart contracts. According to this measurement a doctor can set the problem with the cardiovascular system.
Kidneys are one of the vital organs in human body. They perform the function of filter in the human’s organism. They clean the blood, and evacuate the body from the waste and extra fluid. They control the chemical balance of the body. Changes in the kidneys, connected with the age, refer to the diminution of the kidney tissue. Kidneys contain filtering cells responsible for blood filtration from waste material. Blood vessels delivering kidneys sometimes get indurated. That is the reason why they clean blood not that fast as at the young age.
It is commonly known that the human’s body inclined to corpulence. It may be caused by the lifestyle a person leads as well as the internal and external factors. Body receives less vitamins and minerals, and because of the impurity of the organs by food, alcohol, smoking, etc, the body may get old faster. Healthy in this case means identical to young. To slow down the process of aging, human’s body should get more healthy food; add vitamins and minerals or other supplement nutrition. They will assist in work of the particular organs and body as a whole.
Diarrhea is an illness caused by intestinal infections. It is the main factor in mortality and sickness rate worldwide. The diarrhea is connected with infectious agent: bacteria, parasites, and viruses.
Cholera is an enteric infection induced by Vibrio cholerae. The illness can be mild and asymptomatic. Dehydration and death are caused by severe cholera. The preference in management of the diarrhea is displacing the lost liquid and electrolytes and supply with an antimicrobial agent.