Blood is a tissue that is found in liquid state, consisting of a liquid part (plasma – 55%) and a solid one (45% figurative cells), which circulates in a closed system (the circulatory system). Compared to other tissues, blood cells are not immobilized, they “float” in a viscous fluid (plasma). Because of this, blood is a mobile tissue that manages to sneak in all the human body parts. The main feature of blood is the constant maintenance of the composition and properties of the internal environment. On the other hand, blood components are very mobile and they can quickly indicate any abnormal changes in the body. This is why blood is one of the most investigated biologic fluids of the body.
The functions of blood in the human body
Respiratory function: transport of oxygen required for biological oxidation and the transport of CO2 resulting from oxidation
Nutrition function: blood transports nutrients such as glucose, amino acids, fatty acids, vitamins, resulting in end products of the trophic digestive stage, from the small intestine through the blood capillaries to the liver, to the general circulation and last, to the tissues.
The excretion function is achieved through the transport mechanism of the final catabolic products in the intermediate metabolism
The body’s defense function: blood has the ability to carry the substances involved in specific and nonspecific defense actions. By the antibody proteins lymphocytes, macrophages and plasmocytes, the blood provides immune processes against infectious agents – viruses and bacteria
The function of hemostasis: platelets may cause bleeding to stop at the level of a small or medium blood vessel.
Blood is composed of plasma and figurative elements. Plasma is a notion that designates the liquid fraction of blood and lymph. In plasma, blood cells (red blood cells, white blood cells, platelets) are suspended. Plasma consistes of water, dissolved anorganic substances (mineral salts) and various organic substances (lipids, carbohydrates). Plasma serves as a vehicle for both cellular blood cells and for various biologically active substances (hormones, antibodies, etc.).
The cellular component of blood is represented by:
Erythrocytes (red blood cells) – abbreviated RBC. The erythrocyte is an anuclear cell, carrying a pigment called hemoglobin. Hemoglobin is the heteroprotective blood cell pigment, which, through its physicochemical properties, provides elemental function of ions (O2 and CO2).
Leukocytes (white cells) – abbreviated WBC are nucleated cells with particularly important roles in defense processes, phagocytosis, antibody production and the destruction of microbial toxins.
Platelets are the smallest blood cells, anucleate, that are born in the bone marrow. The function of platelets is to participate in haemostasis by developing coagulation factors. They have a short life of approximately one week.
Essential nutrients for blood cell production
Proteins are the building blocks of the human body. From a chemical point of view, proteins are composed of carbon, hydrogen, nitrogen and oxygen that combine to give rise to the amino acid chains. Along with carbohydrates and lipids, proteins are included in the nutritional class of macronutrietns. The human body uses proteins to build, repair and maintain functional almost all tissues, this includes blood. Proteins are the main building material used to form the globin part of haemoglobin.
Unlike animals, the human body can not synthesize vitamin C alone, which is why it needs to take its dose from food and supplements. Vitamin C is a powerful antioxidant that prevents the action of free radicals (compounds resulting from oxidation processes but also from contact with agents or pollutants) on the body. Accumulation of free radicals in the body is dangerous over time because it is one of the factors contributing to aging and also to the occurrence of cardiovascular disease. Vitamin C is found in high concentrations in the brain, leukocytes, eyes or in the spleen. They have vitamin C concentrations 10 to 50 times higher than those in plasma, red blood cells or saliva. Therefore, when a vitamin C deficiency occurs, these are the first affected organs. Vitamin C also plays a key role in the absorption of Iron. The body requires iron to produce hemoglobin, which is a substance found in erythrocytes that carries oxygen from the lungs to all the cells of the body. Without enough iron, the body produces smaller and less red blood cells. The result is a lower available amount of hemoglobin and thus, the cells of the body will not be fed with sufficient oxygen. Thus, you can clearly understand the correlation between vitamin C, iron, and the key role they play in the general health of the human body.
folic acid is a component of the vitamin B group, working with vitamin B12 in preventing anemia. In case of folic acid deficiency in pregnant women, especially during first months of gestation, there is a risk of birth defects in the newborn. If the body receives enough folic acid, it will exert a protective role on the embryo, especially against neural tube defects and possibly against malformations of the oral cavity. The need for a pregnant woman is around 400 micrograms of folic acid per day, which is brought either by food or nutritional supplements, or by combining them. The deficiency of vitamin B12, also known as cobalamine results in the accumulation of an enzyme which may cause an alteration of DNA synthesis. The end result is a disruption in the maturation of red blood cells. The consequence is the occurrence of megaloblastic anemia that can be associated with irreversible central nervous system damage. Vitamin B12 is also very important for the synthesis of hemoglobin.
A liposoluble vitamin obtained from two classes of compounds: preformed natural vitamin A – retinol and its compounds; precursors of vitamin A (provitamin A) – beta-carotene and related compounds. Retinol is indispensable to vision and it plays a key role in tissue growth, reproduction, embryonic development, glycoprotein synthesis, cancer prevention and cardiovascular disease. Vitamin A increases immunity by decreasing the risk of infections. The recommended daily dose is 800 micrograms in women, children under 10 years and elderly. In men, adolescents and pregnant women, the recommended daily dose is 1000 micrograms. Vitamin A deficiency occurs in a poor diet in dairy and vegetable products or in malabsorption syndromes. This is the main cause of blindness due to the cornea destruction in underdeveloped countries. Among the manifestations of Vitamin A deficiency are degenerative changes in the eyes and skin, due to the fact that the body is no longer able to efficiently control tissue growth.
Blood conditions with genetic transmission
Minkowski-Chauffard disease is a genetically transmited disease with chronic evolution that affects both sexes equally. Hemolysis (destruction of the erythrocytes) is due to the spherical form of erythrocytes that generates increased fragility, seizure and premature destruction in the spleen. The first signs appear in childhood in the form of lice and are characterized by jaundice or subicter, splenomegaly and constitutional abnormalities. Sometimes acute hemolysis occurs: vomiting, fever, abdnominal pain, tachycardia, palpitations. Blood tests reveal anemia, low globular resistance. The number of reticulocytes (the precursors of erythrocytes) is greatly increased.
Erythrocytosis or hereditary ovalocytosis is also a familial disease which is based on an anomaly of the erythrocyte membrane, with the appearance of elongated erythrocytes. 90% of the cases are asymptomatic. Spleen can sometimes be increased in size and in some cases, hemolytic syndrome also occurs.
Hemoglobinopathies are hereditary disorders that are based on deficiency of Hemoglobin synthesis as a consequence of a genetic abnormality in globin formation. Adult Hemoglobin is replaced with abnormal Hemoglobin. Of the hemoglobinopathies, the most common are:
Thalassemia syndromes occurre in first few months or years of life and evolve with signs of hemolysis(destruction of red blood cells), jaundice, marked splenomegaly. The prognosis is reserved. Blood cell transfusions, folic acid and splenectomy may partially alleviate the disease.
Whether we are female or male, adult or child, the choices we make in life have had and will always have a great impact on our lives and our general health. Our body is a perfectly adapted machine but in some cases it needs to be helped through health supplements and through a diet suited for our needs. I can not stress enough the effectiveness of sport and exercise on our well being. Exercising and receiving the much needed nutrients translates in a state in which we no longer have to trouble ourselves with questions related to diseases. The key to a healthy mind is having a healthy body. Exercising daily will prevent cardiovascular diseases, diabetes and will give you a sense of well being. By exercise, our bodies produce more blood cells, our normal resting pulse drops and our brain is more oxygenated. Exercising will help us maintain our calm in difficult situations. Being healthy and staying that way is a choice we all have to make in order to get the most out of our lives.
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