Blood - a special liquid fabric in red, slightly alkaline reaction, constantly moving through the blood vessels of a living organism. In humans, the amount of blood is 1 / 13, body weight, ie, the adult of about 5 - 6 liters, and a teen - 3 liters.
If you take a human blood is placed in a dry tube, and by protecting it from clotting, give it to stand, it will split into two layers. Top layer is composed of a transparent light-yellow fluid - plasma (about 60% of blood volume) and below - deposit of blood cells. In blood plasma is the set of simple and complex substances. 90% of plasma is water, and only 10% of it falls on the dry residue. But as the diversity of its composition! Here and complex proteins (albumin, globulin and fibrinogen), fats and carbohydrates, metals and halides - all elements of the periodic table, salts, alkalis and acids, and various gases, vitamins, enzymes, hormones, etc.
Any substance contained in blood plasma and has a definite and important. Proteins - the building brand name viagra material of our body, fats and carbohydrates - energy sources. Salts, alkalis and acids maintain constant internal environment, a change which is life threatening. Enzymes, vitamins and hormones provide the correct metabolism, growth, development and mutual influence of the organs and systems.
What are the cells - blood cells? This red blood cells - red cells, white blood cells - white blood cells and platelets - platelets.
The bulk of blood cells - red blood cells. They perform a very important function - to carry oxygen. This tiny, visible only under a microscope balls, flattened in the middle in the form of biconcave disk. They resemble a very thin sponge, all the pores which are filled with a special substance - hemoglobin, easy and exciting as it is easy to supply-side Lucky oxygen and carbon dioxide. Red blood cells contain 60% water and 40% solids. 90% of the dry residue accounted for hemoglobin, the remaining 10% consists of proteins, sugars, salts and a variety of other substances contained in blood plasma. The diameter of the erythrocyte - 7-8 microns (a micron is 0,001 mm), width - about 2 microns.
In 1 mm3 of blood contained 4-5 million red blood cells, but only in human blood of their 25 trillion. This is a huge number with 12 zeros: 25 000 000 000 000! If we put all the red cells to each other, you get "stacked" in height at 62 thousand miles - on the axis of this length would rotate a few such planets, like our Earth.
The total surface of all red blood cells at 3800 m2. This is 1500 times greater than the entire surface of the human body. A huge total surface of red blood cells to help them capture and transfer an amount of oxygen that provides full life activity of all organs and tissues. Transport of oxygen - so important task, that most valuable of its execution human red blood cells in the development process even lost their cell nuclei and can no longer reproduce themselves. But place them in the nucleus is filled with hemoglobin, and therefore human red blood cells can capture more oxygen than the red blood cells of lower animals such as frogs. So at higher levels of individual animal cells "sacrifices itself" around the living organism.
Fill the lack
Decision making
ไม่มีความคิดเห็น:
แสดงความคิดเห็น