Lymphatic and cardiovascular system

• Transporting functions of the blood


  • Gasses in solution- O2 lungs -> tissues. CO2 tissues-> lungs
  • Nutrients- amino acids, fatty acids, glucose. Digestive systems -> liver and other tissues
  • Wastes- urea and creatinine. Tissues -> kidneys and livers
  • Hormones/enzymes- endocrine glands -> target tissues
• Regulatory functions of the blood


  • Volume/constituents- water as plasma, maintains osmotic pressure, albumin -> flow of fluid, maintaining pressure in vessels
  • Temperature- conducts heat around body
  • Acid-base balance- maintains pH by buffers
  • Immunity - WBC, antibodies
• Components of blood and their percentage and function

  • 55% plasma
  • 45% erythrocytes - RBC
  • <1% leukocytes/thrombocytes
• Dissolved substances in plasma


  • Mineral salts, sodium, chloride, potassium, calcium, magnesium, bicarbonate
• How RBC are formed


  Stem cells- erythroblasts-> normoblasts -> reticulocytes (howell-Jolly bodies)
• Low oxygen count


  Kidneys will secrete erythropoietin, erythropoietin will stimulate erythropoiesis in the bone marrow, more RBC
• Granulocytes and their specialization


  • Neutrophils- 90% of granulocytes. Move from vessels to surrounding tissues
  • Eosinophils- regulation of allergic reactions, inactivation of inflammatory processes
  • Basophils- histamine (increases inflammation) heparin (natural coagulant)
• Agranulocytes and their specialization


  • Lymphocytes- second most common WBC, main immunity cell
  • B lymphocytes- produce antibodies for humoral response
  • Monocytes- largest WBC, horse-shoe nutrients
• Cascade mechanism of blood clotting


  1. Thromboplastin- platelets accumulate at the site while releasing enzymes

  2. Prothrombin- converted into thrombin

  3. Fibrinogen- converted into fibrin, will need Ca+

  4. Clot- fibers form a network to block the opening, aka a scab
• Path blood takes through the heart

  Vena cava -> Right atrium -> tricuspid valve -> right ventricle -> pulmonary valve -> pulmonary veins -> left atrium -> bicuspid valve -> left ventricle -> aortic valve -> aorta -> body
• Conduction in the heart


  1. Sinoatrial Node goes in the right atrium and allows atrial systole

  2. Atrioventricular Node moves the AV node at the top of the interventricular septum

  3. Bundle of HIS progresses down the septum between ventricles and divides at the bottom

  4. Purkinje fibers spread throughout the ventricular muscles allowing ventricular systole
• Components of the lymphatic system


  • Capillaries- thin and delicate, villi of small intestine, collect products of fat digestion
  • Vessels- result of merging capillaries, contain valves
  • Ducts- drain lymph back to blood circulation. Right lymphatic duct- right side of head, neck, thorax, and forelimb. Thoracic duct- upper left and forelimb, abdomen, pelvis, hindlimbs. Tracheal ducts- drain head and neck
  • Lymph nodes- mass of lymphoid tissue, bean shaped. Flow through spaces
• Lymphatic tissues and their functions


  • Spleen- largest, non essential. Function for storage of blood, destruction of worn out cells, particulate removal, production of lymphocytes
  • Thymus- essential to young animals, responsible for T cell production, regresses at puberty
  • Tonsils- ring around the junction of pharynx and oral cavity. First line of defense
• Differences between nonspecific and specific immune response


  • Humoral produces antibodies (B lymphocytes), antigen stimulates antibody production
  • Cell-mediated immune response- T lymphocytes, non-self cells or altered self-cells