JК
Английский язык :: Беликова Елена
Страница: 23 из 68Lymphocytes are generally small cells measuring 7 – 10 mm in diameter and constitute 25–33 % of , leukocytes. They con tain circular dark-stained nuclei and scanty clear blue cyto plasm. Circulating lymphocytes enter the blood from the lymphatic tissues. Two principal types of immunocompetent lymphocytes can be identified T lymphocytes and В lymphocytes.
T cells differentiate in the thymus and then circulate in the peripheral blood, where they are the principal effec tors of cell-mediated immunity. They also function as helper and suppressor cells, by modulating the immune response through their effect on В cells, plasma cells, macrophages, and other T Cells.
В cells differentiate in bone marrow. Once activated by contact with an antigen, they differentiate into plasma cells, which synthesize antibodies that are secreted into the blood, intercellular fluid, and lymph. В lymphocytes also give rise to memory cells, which differentiate into plas ma cells only after the second exposure to the antigen. Monocytes vary in diameter from 15–18 mm and are the largest of the peripheral blood cells. They constitute 3–7 % of leukocytes.
Monocytes possess an eccentric nucleus. The cytoplasm has a ground-glass appearance and fine azurophilic granules.
Monocytes are the precursors for members of the mo-nonuclear phagocyte system, including tissue macrophages (histiocytes), osteoclasts, alveolar macrophages, and Kupffer cells of the liver.
New words
mesodermal – мезодермальный
erythrocytes – эритроциты
leukocytes – лейкоциты
fibrous proteins – волокнистые белки
immune – иммунный
humoral – гуморальный
to contain – содержать
nuclei – ядра
20. Plasma
Plasma is the extracellular component of blood. It is an aqueous solution containing proteins, inorganic salts, and organic com pounds Albumin is the major plasma protein that maintains the osmotic pressure of blood. Other plasma proteins include the globulins (alpha, beta, gamma) and fibrinogen, which is necessary for the formation of fibrin in the final step of blood coagulation Plasma is in equilibrium with tissue interstitial fluid through capil lary walls; therefore, the composition of plasma may be used to judge the mean composition of the extracellular fluids Large blood proteins remain in the intravascular compartment and do not equilibrate with the interstitial fluid Serum is a clear yellow fluid that is separated from the coagulum during the process of blood clot formation.
T cells differentiate in the thymus and then circulate in the peripheral blood, where they are the principal effec tors of cell-mediated immunity. They also function as helper and suppressor cells, by modulating the immune response through their effect on В cells, plasma cells, macrophages, and other T Cells.
В cells differentiate in bone marrow. Once activated by contact with an antigen, they differentiate into plasma cells, which synthesize antibodies that are secreted into the blood, intercellular fluid, and lymph. В lymphocytes also give rise to memory cells, which differentiate into plas ma cells only after the second exposure to the antigen. Monocytes vary in diameter from 15–18 mm and are the largest of the peripheral blood cells. They constitute 3–7 % of leukocytes.
Monocytes possess an eccentric nucleus. The cytoplasm has a ground-glass appearance and fine azurophilic granules.
Monocytes are the precursors for members of the mo-nonuclear phagocyte system, including tissue macrophages (histiocytes), osteoclasts, alveolar macrophages, and Kupffer cells of the liver.
New words
mesodermal – мезодермальный
erythrocytes – эритроциты
leukocytes – лейкоциты
fibrous proteins – волокнистые белки
immune – иммунный
humoral – гуморальный
to contain – содержать
nuclei – ядра
20. Plasma
Plasma is the extracellular component of blood. It is an aqueous solution containing proteins, inorganic salts, and organic com pounds Albumin is the major plasma protein that maintains the osmotic pressure of blood. Other plasma proteins include the globulins (alpha, beta, gamma) and fibrinogen, which is necessary for the formation of fibrin in the final step of blood coagulation Plasma is in equilibrium with tissue interstitial fluid through capil lary walls; therefore, the composition of plasma may be used to judge the mean composition of the extracellular fluids Large blood proteins remain in the intravascular compartment and do not equilibrate with the interstitial fluid Serum is a clear yellow fluid that is separated from the coagulum during the process of blood clot formation.