6.The skeleton and muscles.
The skeleton is composed of bones. In the adult the skeleton has over 200 bones. The bones of the skull consist of cranial and facial parts. The bones of the trunk are the spinal column or the spine and the chest. The spine consist of the cervical, thoracic, lumbar and sacral vertebrae and the coccyx. The chest composed of 12 thoracic vertebrae the breastbone and 12 pairs of ribs. On each side of the chest seven ribs are not connected with the breastbone either. The bones consist of organic and inorganic substance. The cartilages are connected bones. Muscles are attached to bones. The body was composed of about 600 skeletal muscles. All the muscles were divided into three basic groups: long, short and wide muscles; the free extremities were formed by the long muscles; wide muscles lay on the trunk; the walls of the body cavities were formed by wide muscles. The muscles were the active agents of motion and contraction.
7.The physiology of the cardiovascular system.
Cardiovascular system consists from heart and blood vessels. The heart is a muscular organ, composed primarily of cardiac muscle tissue, which contracts rhythmically to pump blood throughout the body. Cardiac skeleton is composed mainly of dense connective tissue and consists of the annuli fibrosi, the trigonum fibrosum, and the septum membranaceum. Cardiac valves are composed of dense fibrous tissue covered by endothelium. The human heart contracts from the first moment of life until the last one. The contractions of the heart pump the blood through the arteries to all the parts of the body. Each beat of the heart is followed by a period of rest for the cardiac muscle. Each wave of contraction and a period of rest following it compose a cardiac cycle. Blood circulates in vessels. Blood is composed of plasma and the corpuscular elements which are called red corpuscles or erythrocytes, white corpuscles or leucocytes and blood platelets.
8.The physiology of the lungs is associated with their structure. There are over 700,000,000 alveoli in the lungs. The total surface of the alveoli is about 90 sq. m (square metres). The lungs have many capillaries with the total surface of about 80 sq. m. This particular structure of the lungs enables the exchange of gases between the alveolar air and the blood.
Elastic fibers of connective tissue composing the walls of the alveoli, alveolar passages and the visceral pleura enable the lungs to dilate.
The regulation of the vital capacity of the lungs is of particular importance to the exchange of oxygen and carbon dioxide taking place in the lungs. It is considered that in the adult the vital capacity of the lungs is about 3-4 litres. When the depth of respiration increases the vital capacity may be 6 litres and even more.
The lungs take part in the production of physiologically active substances, in the regulation of blood coagulation, in the metabolism of proteins, fats and carbohydrates.
9.The physiology nervous system.
Brain - the main component of nervous system. Our brain is the most complicated mechanism. It has consists of about 12 billion cells. Each cell is connected to the other directly or indirectly by nerve fibers. A constant flow of stimuli comes into the brain through the spinal cord. The stimuli come to the brain from our eyes, ears, and other sense organs for pain, temperature, smell and other feeling. When all the received stimuli have been summarized and analysed the brain sends orders through the nerve fibers in the spinal cord to different parts of the human body. During a sound quiet sleep the whole activity of the human organism changes, the body metabolism decreases, and the respiratory and pulse rates become slower, the body temperature drops. Though the stimuli continue to come into the brain, the inhibited cortical cells do not react to them.
10.Tracheitis [.treiki'aitis] is the disease in which the mucous membrane of the trachea [trs'kia] is impaired. The disease usually develops in a weak organism, after a person has been in the cold environment for a long period of time, or after some infectious disease.
In such conditions the microorganisms such as pneumocooci, staphylococci and streptococci which usually invade the upper respiratory tract, multiply-rapidly and produce the inflammation of the mucous membrane.
The main symptom of tracheitis is the cough, usually dry at first. After the attack of cough the patient feels pain in the substernal area and in the throat. The general condition becomes worse. In the adults the temperature may not be high, but in the children it may be as high as 39°C.
The patient with tracheitis usually follows home treatment receiving a sick-leave for the period of his disease. The patient must be in a warm room well aired. He may be administered aspirin or codein which gives some relief. He may also be recommended to have warm milk with soda several times a day.