Cardiovascular System 11-1 to 11-4 By: Jaina and Sam U.

Blood 11-1 5 Major Functions…CQ#1 Transports dissolved gases, nutrients, hormones, and metabolic wastes Regulates pH and ion makeup of interstitial fluids Restricts fluid loss at injury sites Defends against toxins and pathogens Stabilizes body temperature Circulating fluid of the body

Whole Blood Made up of plasma and formed elements(blood cell fragments) CQ#2 Components of whole blood may be separated Blood is five times as viscous as water

Collection and Analysis Collected from a superficial vein on the anterior surface of the elbow This is called venipuncture It is a common technique for obtaining blood Superficial veins are easy to find, the walls of the veins are thinner than those of arteries of comparable size, and blood pressure in the venous system is relatively low CQ#3 Arterial puncture may be required for evaluating the efficiency of gas exchange at the lungs

Plasma 11-2 Three Major Types of Plasma Proteins Albumins, Globulins, and Fibrinogen CQ#4 Makes up the greatest volume of whole blood Decreased amounts of plasma proteins would cause liver disorders which can alter the composition and functional properties of the blood CQ#5 Albumins make up the majority of the plasma proteins Globulins include antibodies and transport proteins Fibrinogen functions in blood clotting

Red Blood Cells 11-3 RBCs (red blood cells) contain pigment of hemoglobin which binds and transports oxygen and carbon dioxide CQ#6 A single drop of whole blood contains some 260 million RBCs Hematocrit- the percentage of whole blood volume occupied by formed elements The Hematocrit increases during dehydration CQ#7 The shape gives each RBC a large surface area to volume ratio that increases the rate of diffusion Enables RBCs to bend and flex to squeeze through narrow capillaries

Hemoglobin Two pairs of globular proteins combine to form a single hemoglobin molecule Heme- each of the four subunits contains a single molecule of an organic pigment Anemia- the blood of a person who has a low hematocrit, or whose RBCs have reduced hemoglobin content, has reduced oxygen-carrying capacity

Hemoglobin Recycling Four globular proteins are broken apart into amino acids Each heme is stripped of its iron and converted to biliverdin-organic compound with a green color, biliverdin is then converted to bilirubin-orange pigment and released into bloodstream, Liver cell absorbs the bilirubin and releases it into the small intestine, if bile ducts are blocked bilirubin then diffuses into peripheral tissues Iron extracted may be stored in the bloodstream where it binds to transferrin- plasma transport protein

CQ#8 Bilirubin is a byproduct of the normal breakdown of red blood cells. It usually passes through the liver and is flushed, but if this doesn’t occur due to liver disease, bilirubin levels in the blood can rise and the skin can take on the yellow discoloration known as jaundice.

Regulation of Erythropoiesis To proceed normally the red bone marrow must receive supplies of amino acids, iron, and vitamins Normal stem cell divisions cannot occur without vitamin B12 Erythropoiesis- stimulating hormone Effects- 1. it stimulates increased cell division rates in erythroblasts and in the stem cells that produce erythroblasts 2. it speeds up maturation of RBCs Reduction in oxygen levels supplied to the kidneys raises the levels of erythropoietin in the blood CQ#9

ABO blood types and Rh System Antigens- substances that can trigger a protective defense mechanism called and immune response The presence or absence of specific surface antigens determine your blood type You can be Rh positive or Rh negative A person with type AB can receive from all other blood types CQ#10

Cross-Reactions in Transfusions Plasma of individuals with type A contains circulating anti-B antibodies which will attack type B surface antigens CQ#11 AB individuals lack antibodies against either A or B Type O contains both a and B antibodies