TORTORA CARDIO

• What is the focus of this chapter?

  The focus of this chapter is blood.
• What are the primary functions of blood?


  Blood transports substances, regulates life processes, and provides protection against disease.
• How is blood unique among individuals?


  Blood is unique from one person to another, similar to skin, bone, and hair.
• Why do health-care professionals analyze blood?


  They analyze blood to determine the cause of different diseases.
• How does blood contribute to homeostasis?


  Blood transports oxygen, carbon dioxide, nutrients, and hormones, and regulates pH and temperature.
• What is the temperature of blood?


  The temperature of blood is 38°C (100.4°F).
• What is the pH range of blood?


  The pH of blood ranges from 7.35 to 7.45.
• What happens to the color of blood when it is saturated with oxygen?


  When saturated with oxygen, blood is bright red.
• What percentage of extracellular fluid does blood constitute?


  Blood constitutes about 20% of extracellular fluid.
• What is the average blood volume in an adult male?


  The average blood volume in an adult male is 5 to 6 liters.
• What is the average blood volume in an adult female?


  The average blood volume in an adult female is 4 to 5 liters.
• What regulates blood volume and osmotic pressure?

  Several hormones regulated by negative feedback ensure blood volume and osmotic pressure remain constant.
• What are the three hormones important for regulating blood volume?


  The hormones are aldosterone, antidiuretic hormone, and atrial natriuretic peptide.
• What are the common methods for withdrawing blood for laboratory testing?

  • Venipuncture: withdrawal from a vein using a needle.
  • Finger or heel stick: often used for diabetic patients and infants.
  • Arterial stick: used to determine oxygen levels in blood.
• What are the two main components of whole blood?


  The two main components are blood plasma and formed elements.
• What happens when blood is centrifuged?


  The cells sink to the bottom while the plasma forms a layer on top.
• What percentage of blood is formed elements?


  Blood is about 45% formed elements.
• What percentage of blood is plasma?


  Blood is about 55% plasma.
• What are the three principal components of formed elements in blood?


  The three principal components are red blood cells, white blood cells, and platelets.
• What is the function of red blood cells (RBCs)?


  RBCs transport oxygen from the lungs to body cells and carbon dioxide from body cells to the lungs.
• What is the function of white blood cells (WBCs)?


  WBCs protect the body from invading pathogens and foreign substances.
• What are the types of white blood cells (WBCs)?


  The types of WBCs include neutrophils, basophils, eosinophils, monocytes, and lymphocytes.
• What is the role of platelets in blood?


  Platelets release chemicals that promote blood clotting when blood vessels are damaged.
• What is hematocrit?


  The percentage of total blood volume occupied by red blood cells.
• What is the normal range of hematocrit for adult females?


  The normal range is 38–46%.
• What is the normal range of hematocrit for adult males?


  The normal range is 40–54%.
• How does testosterone affect hematocrit levels?


  Testosterone stimulates the synthesis of erythropoietin, which increases RBC production and hematocrit levels.
• What is hemopoiesis?


  Hemopoiesis is the process by which the formed elements of blood develop.
• Where does hemopoiesis first occur before birth?


  Hemopoiesis first occurs in the yolk sac of an embryo.
• What is the primary site of hemopoiesis after birth?


  The primary site of hemopoiesis after birth is red bone marrow.
• What is the composition of red bone marrow?

  Red bone marrow is a highly vascularized connective tissue located in the spaces between trabeculae of spongy bone tissue.
• What percentage of red bone marrow cells are pluripotent stem cells?


  About 0.05–0.1% of red bone marrow cells are pluripotent stem cells.
• What happens to red bone marrow as an individual ages?


  As an individual ages, the rate of blood cell formation decreases, and red bone marrow becomes inactive and is replaced by yellow bone marrow.
• What is yellow bone marrow primarily composed of?


  Yellow bone marrow consists largely of fat cells.
• Under what condition can yellow bone marrow become active?


  Yellow bone marrow can become active under conditions such as severe bleeding.
• What are the functions of blood?


  1. Transportation: Carries oxygen, carbon dioxide, nutrients, hormones, heat, and wastes.
  2. Regulation: Maintains homeostasis, regulates pH, body temperature, and water content of cells.
  3. Protection: Clots to prevent blood loss and protects against disease through immune responses.
• What are the components of blood plasma?


  • Water (91.5%)
  • Plasma proteins (7%): Albumins, globulins, fibrinogen
  • Other solutes (1.5%): Electrolytes, nutrients, gases, regulatory substances, waste products
• What are the types of white blood cells and their roles?


  • Neutrophils: Fight infections
  • Lymphocytes: B cells, T cells, NK cells for immune response
  • Monocytes: Differentiate into macrophages
  • Eosinophils: Combat parasites
  • Basophils: Release histamine in allergic reactions
• What is red bone marrow primarily composed of?


  Highly vascularized connective tissue
• Where is red bone marrow chiefly located?


  In the axial skeleton, pectoral and pelvic girdles, and proximal epiphyses of the humerus and femur