Circulatory System: Blood

Both include heart and blood vessels but circulatory system has blood

• Carry oxygen from lungs to body's tissues
• Carry carbon dioxide from tissue to lungs
• Carry metabolic waste to the kidneys
• Carry hormones from glands to target organs
• Transport stem cells from bone marrow to target tissues

• Inflammation processes – prevents spread of infection
• White blood cells destroy microorganisms and cancer cells
• Antibodies neutralize toxins and destroy pathogens
• Platelets secrete clotting factors

• Capillaries distribute fluid evenly in body
• Buffer pH of extracellular fluids
• Regulate body temperature

Plasma and Formed Elements

Fluid basis of blood ("matrix")

• Cells and cell fragments
• Erythrocytes (red blood cells): % = hematocrit
• Platelets
• Leukocytes (white blood cells)
• Granulocytes: neutrophils, eosinophils, basophils
• Agranulocytes: lymphocytes and monocytes.

Put in a centrifuge to spin them out, cells are heavier and sink, Plasma is on top with 55%, Buffy coat of leukocytes in the middle, and 45% erythrocytes at the bottom

Water, protein, nitrogenous compounds, nutrients, gases, electrolytes, and hormones.

Primary plasma protein; transports solutes, buffers pH

Plasma protein that transports solutes and has immune functions

Plasma protein that promotes clotting (plasma minus fibrinogen = serum)

• Free amino acids (dietary protein or tissue)
• Nitrogenous wastes (urea produced by catabolism)

• Glucose, vitamins, fats, cholestorol, phospholipids, minerals
• Dissolved O2, CO2, and nitrogen
• Electrolytes (primarily Na+)

• Resistance of fluid to flow due to cohesion of particles
• Viscosity of blood is a result of the red blood cells and protein
• Proper viscosity is important for blood flow through circulatory system

• A measure of the number of particles that can't pass through blood vessel walls
• If too high, blood absorbs too much water (increasing blood pressure)
• If too low, blood doesn't absorb enough water (decreasing blood pressure)

• Extreme protein deficiency decreases osmolarity
• Fluid moves into interstitial spaces.

• Production of blood, especially formed elements
• Average adult produces 400 billion platelets, 200 billion RBC, 10 billion WBC every day

• Yolk Sac: stem cells for first blood cells
• Liver: until birth
• Spleen: lymphocytes
• Red Bone Marrow: all formed elements
• Thymus: T Cells

• Carry oxygen from lungs to tissues throughout body
• Carry carbon dioxide from tissues to lungs

• Increased surface area/volume for lots of gas diffusion across membrane
• Cells are flexible to get through narrow capillaries
• Lots of hemoglobin (280 million molecules per RBC) to help carry oxygen and carbon dioxide
• Lots of carbonic anhydrase in cytoplasm to neutralize carbon dioxide

• One Molecule: Four globulins, four heme groups (bind oxygen)
• Heme binds O2 when O2 levels are high (lungs), releases it when O2 levels are low (tissues)

• Hematocrit: percentage of blood composed of RBC
• Hemoglobin concentration: percentage of blood composed of hemoglobin
• RBC count
• Higher RBC/hemoglobin amounts mean blood can carry more oxygen

• Hematocrit, hemoglobin concentration, and RBC count lower in women
• Androgens stimulate RBC production
• Women have periodic menstrual loss
• Hematocrit inversely proportional to percentage of body fat

• 2.5 million RBCs produced per second
• Average lifespan of 120 days
• Development takes 3-5 days: Reduction in size, synthesis of hemoglobin, loss of nucleus

• Iron: Part of Heme group
• Vitamin B12 and Folic Acid: needed for rapid cells division and DNA synthesis
• Vitamin C and copper: Cofactors for enzymes synthesizing hemoglobin

• Body doesn't have enough RBCs or hemoglobin
• 3 causes: Inadequate erythropoiesis or hemoglobin synthesis (kidney failure or Iron/Vitamin B12 deficiency), Hemorrhagic causes (bleeding), or hemolytic causes (RBC destruction)

• Tissue hypoxia
• Reduced blood osmolarity (edema)
• Reduced blood viscosity (blood pressure drops)

• Recessive allele modifies shape of hemoglobin
• Hb doesn't bind O2 well
• RBC change shape, clump together, and block blood vessels

• Drop in RBC count causes kidney to stimulate erythropoiesis (through release of erythropoietin)
• Increases cell division rate
• Increases Hb production rate
• Stimulating factors: low O2 levels, high altitude, increase in exercise, loss of lung tissue

• Increasing number of RBCs in an attempt to increase oxygen delivery to muscles
• Originally athletes would inject themselves with their own or donor RBCs
• Now use injection of erythropoietin
• Problems when blood is too viscous, though

• Greenish-yellow bruises a result of biliverdin and bilirubin buildup
• Jaundice is symptom resulting for inability to metabolize or excrete bilirubin

• Based on antigens attached to RBC surface
• Antigen: any molecule that's on the surface of a red blood cell that produces an immune response

• Globulins produce antibodies (agglutinins) to antigens
• Body doesn't produce antibodies to antigens that it naturally has

Clumping of RBC after antibodies bind to antigens on RBC

• Has anti A and anti B
• Receives from: O only
• Universal doner

• Has anti B
• Receives from: A and O

• Has anti A
• Receives from: B or O

• Doesn't have any antibodies
• Can receive any type of blood (universal receiver)

• Rh is another antigen
• The positive or negative part of your blood type
• Rh negative people don't normally produce antibodies against Rh factor

• Rh negative mother, Rh positive baby
• Blood is mixed during birth
• Once exposed, she will start producing anti Rh antibodies
• Can cause red blood cell destruction in the baby.