•Blood performs a number of functions dealing with:
•Regulation of blood levels of particular substances
•Oxygen from the lungs and nutrients from the digestive tract •Metabolic wastes from cells to the lungs and kidneys for elimination Hormones from endocrine glands to target organs
•Appropriate body temperature by absorbing and distributing heat •Normal pH in body tissues using buffer systems
Adequate fluid volume in the circulatory system
•Blood prevents blood loss by:
•Activating plasma proteins and platelets
•Initiating clot formation when a vessel is broken
•Blood prevents infection by:
•Synthesizing and utilizing antibodies
•Activating complement proteins
•Activating WBCs to defend the body against foreign invaders
2.Specify the composition and functions of plasma.
•Blood plasma contains over 100 solutes, including:
•Proteins – albumin, globulins, clotting proteins, and others •Nonprotein nitrogenous substances – lactic acid, urea, creatinine •Organic nutrients – glucose, carbohydrates, amino acids •Electrolytes – sodium, potassium, calcium, chloride, bicarbonate •Respiratory gases – oxygen and carbon dioxide
3. Describe the structure, function, and production of platelets.
•Platelets are fragments of megakaryocytes with a blue-staining outer region and a purple granular center •Their granules contain serotonin, Ca2+, enzymes, ADP, and platelet-derived growth factor (PDGF) •Platelets function in the clotting mechanism by forming a temporary plug that helps seal breaks in blood vessels •The stem cell for platelets is the hemocytoblast
•The sequential developmental pathway is hemocytoblast, megakaryoblast, promegakaryocyte, megakaryocyte, and platelets
4.List the characteristics and functions of red blood cells.