Composition of Blood and its Functions

Text, Important, Lecture quotes 200 points 25 mc, 10 short answer questions, 3 essay questions 1.2.Blood all functions of blood p. 662 a. The blood has 3 functions i. Transportation 1. Transports oxygen from lungs to cells of the body and carbon dioxide form the body to the lungs. It also carries nutrients, gases, waste and hormones. ii. Regulation: 1. Circulating blood helps maintain homeostasis of all body fluids. a. Blood’s ph buffer system b. Body temperature regulation c. Blood osmotic pressure influences the water content of cells. iii. Protection: 1. Blood can clot 2. White blood cells protects against disease by phagocytosis 3. Other proteins help protect the body from disease. Know mesenchymal to blood cells, know derevatives of blood cells 665 a. Hematopoiesis b. Leukopoeisis c. Know steps d. Red bone marrow is a highly vascularized connective tissue located in the microscopic spaces between trabeculae of spongy bone tissue. It is present chiefly in bones of the axial skeleton, pectoral and pelvic girdles, and the proximal epiphyses of the humerus and femur. About 0.05–0.1% of red bone marrow cells are called pluripotent stem cells or hemocytoblasts and are derived from mesenchyme (tissue from which almost all connective tissues develop). e. pluripotent stem cells in red bone marrow produce two further types of stem cells, which have the capacity to develop into several types of cells. These stem cells are called myeloid stem cells and lymphoid stem cells. Myeloid stem cells begin their development in red bone marrow and give rise to red blood cells, platelets, monocytes, neutrophils, eosinophils, basophils, and mast cells. f. The process of producing blood cells is hemopoiesis (hematopoiesis). Pluripotent stem cells differentiate into each of the different types of blood cells. g. During hematopoiesis, some myeloid cells become progenitor cells and other become precursor cell.