Vascular: Anatomy & Physiology

Vessel Types

Arteries

  • Pumps Blood Away from the Heart to Tissues
  • Oxygenation:
    • Pulmonary Arteries: Carry Deoxygenated Blood from Heart to Lungs
    • Systemic Arteries: Carry Oxygenated Blood from Heart to Body Tissues
  • More Muscular than Veins or Lymphatics
  • Vasa Vasorum – Network of Small Blood Vessels that Supply the Walls of Larger Blood Vessels

Veins

  • Drains Blood from Tissues Back to the Heart
  • Types:
    • Deep Veins – Deep in the Body, Typically Correlate with Arterial Supply
    • Superficial Veins – Superficial, Do Not Correlate with Arterial Supply
    • Perforator Veins – Connect Superficial to Deep Veins
  • Oxygenation:
    • Pulmonary Veins: Carry Oxygenated Blood from Lungs to Heart
    • Systemic Veins: Carry Deoxygenated Blood from Body Tissues to Heart
  • Less Muscular than Arteries
  • Veins Have Valves
    • No Valves in Portal Vein, SVC, IVC, or Common Iliacs

Lymphatics

  • Thin Walled Vessels that Drain Lymph Through the Lymphatic System
  • Components:
    • Lymphatic Capillaries: Absorbs Interstitial Fluid & Drains into Afferent Vessels
    • Afferent Vessels: Drain Lymph from Tissues to Lymph Nodes
    • Efferent Vessels: Drain Lymph from Lymph Nodes to Other Lymph Nodes or Veins
  • Very Thin Muscular Layer
  • Deep Lymphatics Have Valves
  • No Lymphatics in Bone, Muscle, Tendon, Cartilage, Brain or Cornea

Vascular Circulation (Pulmonary & Systemic) 1

Vessel Structure

Tunica Adventitia

  • External Layer
  • Composed of Collagen & Elastic Fibers

Tunica Media

  • Middle Layer
  • Composed of Smooth Muscle, Collagen & Elastic Fibers
  • Arteries are Muscular
  • Veins & Lymphatics are Much Less Muscular

Tunica Intima

  • Internal Layer in Contact with Blood
  • Composed of Endothelium

Arterial Wall Layers 2

References

  1. Kebert T, Umimeto.org. Wikimedia Commons. (License: CC BY-SA-4.0)
  2. Ghesquiere SA. Wikimedia Commons. (License: CC BY-SA-2.5)