Blood+DB

Blood

(1) What are the functions of blood, and what are its two main portions? The blood functions to transport oxygen and nutrients, carry away wastes and defend the body against pathogens. The blood contains antibodies and clots to prevent blood loss. Blood also maintains homeostasis by balancing salts and plasma proteins.

(2) What is the composition of plasma and what are the functions of plasma proteins? Blood is 90 % water, and about 9 % different salts and organic molecules. Plasma proteins aid in maintaining homeostasis by creating an osmotic gradient between blood and tissue fluid. Certain plasma proteins also help to transport substances in the blood like cholesterol and hormones.

(3) What substances allow red blood cells (RBCs) to transport oxygen? Hemoglobin allows a red blood cell to carry over a billion copies of oxygen.

(4) Why do RBCs have a biconcave shape? RBSs have a biconcave shape because during maturation, they lose their nucleus. The shape also allows them to have more room to allow gases to diffuse in and out of the cell.

(5) Name and describe three disorders associated with RBCs. Disorders involving red blood cells include: anemia, in which a person becomes tired due to a lack of iron in the cells, Hemolysis, in which red blood cells rupture, and sickle-cell disease, in which red blood cells are sickle-shaped and have a shorter life span.

(6) What are the different blood types and what determines blood type? Blood type is based on the lack or presence of antigens A and B on the surface of red blood cells. The different types include: Type A, Type B, Type AB, and Type O.

(7) Among the ABO types of blood, who can give blood to whom? Why? A person with type A blood (with A antigens) can give blood to a person with Type B blood because it has no A antigens but has A antibodies in it’s plasma. A person with Type B blood can give blood to a person with Type A blood for the same reason. A person with Type O blood can give blood to a person with Type A or Type B blood because Type O has both A and B antibodies in its plasma.

(8) When does hemolytic disease in a newborn occur? Hemolytic disease occurs if a mother with RH- blood gives birth to a child with RH+ blood and some of the baby’s blood cell leak into the mother’s bloodstream. The mother begins producing anti-Rh antibodies, and if she has another Rh- baby, they attack the baby’s red blood cells. The baby’s blood cells continue to destruct after it is born, and mental retardation or even death can result.

(9) Tell how the functions of the cardiovascular system contribute to homeostasis? The Cardiovascular system maintains homeostasis because it furnishes the needs of the body’s cells.

(10) In what way does the liver contribute to the functioning of the cardiovascular system? The liver helps blood cells move waste products out of the body and absorbs water in order to maintain blood pressure.