Blood Powerpoint

• Blood


  Transports everything that must be carried from one place to another through blood vessels, such as: Nutrients, Wastes, Hormones, Body heat

  
• Blood


  The only fluid tissue, a type of connective tissue, in the human body

  
• Components of blood


  • Formed elements (living cells)
  • Plasma (nonliving fluid matrix)

  
• When blood is separated


  1. Plasma rises to the top (55 percent of blood)

  2. Erythrocytes, or red blood cells, sink to the bottom (45 percent of blood, a percentage known as the hematocrit)

  3. Buffy coat contains leukocytes, or white blood cells, and platelets (less than 1 percent of blood)

  
• Blood


  • Sticky, opaque fluid
  • Heavier and thicker than water
  • Oxygen-rich blood is scarlet red
  • Oxygen-poor blood is dull red or purple
  • Metallic, salty taste
  • Slightly alkaline, between 7.35 and 7.45
  • Slightly higher than body temperature, at 38°C or 100.4°F

  
• Blood volume


  About 5–6 liters, or about 6 quarts, of blood are found in a healthy adult<|>Blood makes up 8 percent of body weight

  
• Plasma


  90 percent water<|>Straw-colored fluid<|>Includes many dissolved substances: Nutrients, Salts (electrolytes), Respiratory gases, Hormones, Plasma proteins, Waste products
• Plasma proteins


  Most abundant solutes in plasma<|>Most are made by the liver<|>Include: Albumin—an important blood buffer and contributes to osmotic pressure, Clotting proteins—help to stem blood loss when a blood vessel is injured, Antibodies—help protect the body from pathogens

  
• Blood composition varies as cells exchange substances with the blood

  
• Liver makes more proteins when levels drop
• Respiratory and urinary systems restore blood pH to normal when blood becomes too acidic (acidosis) or alkaline (alkalosis)
• Plasma helps distribute body heat
• Formed elements


  • Erythrocytes (red blood cells, or RBCs)
  • Leukocytes (white blood cells, or WBCs)
  • Platelets (cell fragments)

  
• Erythrocytes (red blood cells, or RBCs)


  Main function is to carry oxygen<|>Anucleate (no nucleus)<|>Contain few organelles; lack mitochondria<|>Make ATP by anaerobic means<|>Essentially "bags" of hemoglobin (Hb)<|>Shaped like biconcave discs<|>Normal count is 5 million RBCs per cubic millimeter (mm3) of blood

  
• Hemoglobin


  Iron-bearing protein<|>Binds oxygen<|>Each hemoglobin molecule can bind 4 oxygen molecules<|>Each erythrocyte has 250 million hemoglobin molecules<|>Normal blood contains 12–18 grams of hemoglobin per 100 milliliters (ml) of blood

  
• Sickle cell anemia (SCA)


  Results from abnormally shaped hemoglobin
• Types of anemia


  • Hemorrhagic anemia, Hemolytic anemia, Pernicious anemia, Aplastic anemia, Iron-deficiency anemia, Sickle cell anemia
• Leukocytes (white blood cells, or WBCs)


  Crucial in body's defense against disease<|>Complete cells, with nucleus and organelles<|>Able to move into and out of blood vessels (diapedesis)<|>Respond to chemicals released by damaged tissues (known as positive chemotaxis)<|>Move by amoeboid motion by forming cytoplasmic extensions to help them move<|>4,800 to 10,800 WBCs per mm3 of blood

  
• Types of leukocytes

  • Granulocytes (neutrophils, eosinophils, basophils)
  • Agranulocytes (lymphocytes, monocytes)
• WBCs from most to least abundant


  • Neutrophils
  • Lymphocytes
  • Monocytes
  • Eosinophils
  • Basophils
• Neutrophils


  Most numerous WBC<|>Multilobed nucleus<|>Cytoplasm stains pink and contains fine granules<|>Function as phagocytes at active sites of infection<|>Numbers increase during infection<|>3,000–7,000 neutrophils per mm3 of blood (40–70 percent of WBCs)
• Eosinophils


  Nucleus stains blue-red<|>Brick-red cytoplasmic granules<|>Function is to kill parasitic worms; play a role in allergy attacks<|>100–400 eosinophils per mm3 of blood (1–4 percent of WBCs)
• Basophils


  Rarest of the WBCs<|>Large histamine-containing granules that stain dark blue to purple<|>Contain heparin (anticoagulant)<|>20–50 basophils per mm3 of blood (0–1 percent of WBCs)
• Lymphocytes


  Large, dark purple nucleus<|>Slightly larger than RBCs<|>Reside in lymphatic tissues<|>Play a role in immune response<|>1,500–3,000 lymphocytes per mm3 of blood (20–45 percent WBCs)
• Monocytes


  Largest of the white blood cells<|>Distinctive U- or kidney-shaped dark purple nucleus<|>Function as macrophages when they migrate into tissues<|>Important in fighting chronic infection<|>100–700 monocytes per mm3 of blood (4–8 percent of WBCs)

  
• Platelets


  Fragments of megakaryocytes (multinucleate cells)<|>Needed for the clotting process<|>Normal platelet count is 300,000 platelets per mm3 of blood
• Table 10.2 Characteristics of Formed Elements of the Blood

  
• Hematopoiesis


  1. The process of blood cell formation

  2. Occurs in red bone marrow (myeloid tissue)

  3. All blood cells are derived from a common stem cell (hemocytoblast)

  4. Hemocytoblasts form two types of descendants: Lymphoid stem cell, which produces lymphocytes, Myeloid stem cell, which can produce all other formed elements
• Formation of red blood cells


  1. RBCs are anucleate, so they are unable to divide, grow, or synthesize proteins

  2. RBCs wear out in 100 to 120 days

  3. When worn out, RBCs are eliminated by phagocytes in the spleen or liver

  4. Lost cells are replaced by division of hemocytoblasts in the red bone marrow

  5. Reticulocytes are young RBCs which enter the blood to become oxygen-transporting erythrocytes
• Erythropoietin


  A hormone that controls the rate of RBC production<|>Kidneys produce most erythropoietin as a response to reduced oxygen levels in the blood
• Homeostasis is maintained by negative feedback
• Lymphoid stem cell


  Produces lymphocytes
• Myeloid stem cell


  Can produce all other formed elements
• Formation of Red Blood Cells (1 of 2)


  1. RBCs are anucleate, unable to divide, grow, or synthesize proteins

  2. RBCs wear out in 100 to 120 days

  3. Worn out RBCs are eliminated by phagocytes in the spleen or liver

  4. Lost cells are replaced by division of hemocytoblasts in the red bone marrow

  5. Reticulocytes are young RBCs which enter the blood to become oxygen-transporting erythrocytes
• Formation of Red Blood Cells (2 of 2)


  1. Rate of RBC production is controlled by erythropoietin

  2. Kidneys produce most erythropoietin as a response to reduced oxygen levels in the blood

  3. Homeostasis is maintained by negative feedback from blood oxygen levels

  
• Formation of White Blood Cells and Platelets


  1. WBC and platelet production is controlled by colony stimulating factors (CSFs) and interleukins

  2. Thrombopoietin stimulates production of platelets from megakaryocytes
• Hemostasis (1 of 6)


  Hemostasis involves vascular spasms, platelet plug formation, and coagulation (blood clotting)
• Hemostasis (2 of 6)


  Vascular spasms: Immediate response to blood vessel injury, vasoconstriction causes blood vessel to spasm, spasms narrow the blood vessel, decreasing blood loss
• Hemostasis (3 of 6)


  Platelet plug formation: Collagen fibers are exposed, platelets become "sticky" and cling to fibers, anchored platelets release chemicals to attract more platelets, platelets pile up to form a platelet plug
• Hemostasis (4 of 6)


  Coagulation: Injured tissues release tissue factor (TF), PF3 interacts with TF, blood protein clotting factors, and calcium ions to trigger a clotting cascade, Prothrombin activator converts prothrombin to thrombin