gross anatomy of circulations

• Function of the circulatory system 

  *Transports:

  • O2
  • Nutrients
  • CO2
  • Metabolic waste
  • Cells of immune system
  • Hormones
• Blood circulatory system 

  *Systemic

  *Pulmonary 

  *Coronary
• Specialised circulatory systems *Coronary

  *Portal

  *Foetal
• Blood circulatory system

  • Closed circuit
  • Arteries carry blood away from the heart. Veins bring blood back
  • Arteries and veins generally equal in distribution
  • Tissues and organs are services by several A. and V. where anastomosisprevent blockages
• Systemic circulation

  • High pressure system (arterial side)
  • Takes oxygen rich blood away from left side of the heart to body tissues
  • Returns oxygen poor blood from the tissues to right side of the heart

  
• Veins

  1. Vena cava is the same as abdominal aorta but deoxygenated
  2. No carotid veins they are jugular
• Pulmonary circulation

  • Low pressure system
  • Involved in heart and lunches
  • Takes oxygen poor blood from right side of the heart to lungs
  • Take oxygen rich blood from lungs to left side of the heart
  • Pulmonary veins= away from the heart`
  • Pulmonary artery = towards the heart
• Portal circulation

  • Hypophyseal portal system = hypothalamus and pituitary gland
  • Hepatic portal system = gastrointestinal tract and liver
• Lymphatic system*Composed of: Lymph vessels, Lymph and lymphatic tissues and organs

  *Functions: Body defence mechanisms and Drainage of interstitial fluid

  • Interstitial fluid = plasma helps carry nutrients and ions, some will leak out ofcapillaries. Fluid moves into interstitial space at arteriole end of the capillary and moves back at venous end
  • Left behind = development of oedema
  • Excess fluid back into blood via lymphatic system via lymphatic capillary, onceit's in the capillary it is no longer plasma it is lymph
• Lymphatic drainage:

  1. Lymph capillaries
  2. Lymph vessels (Via lymph nodes = filter lymph via lymphocytes and macrophages)
  3. Lymph trunk
  4. Thoracic duct and right lymphatic duct
• Lymph nodes

  • Encapsulated aggregations of lymphocytes located in lymphatic vessels
  • Filter lymph and trap foreign particles
  • Some particles destroyed by macrophages
• Lymphatic drainage

  • Right side of the head, neck, thorax and upper limb → right lymphatic duct → right subclavian vein
  • Rest of the body → thoracic duct → left subclavian veins
  • All goes back into blood once drained