Birds and mammals have fully separated pulmonary and systemic circuits

The four-chambered hearts of birds and mammals completely separate their pulmonary and systemic circuits. Separate circuits have several advantages:

► Oxygenated and deoxygenated blood cannot mix; therefore, the systemic circuit is always receiving blood with the highest oxygen content.

► Respiratory gas exchange is maximized because the blood with the lowest oxygen content and highest CO2 content is sent to the lungs.

► Separate systemic and pulmonary circuits can operate at different pressures.

Lung

Lung

Pulmonary Circuit And Systemic Circuit

Pulmonary circuit

Left ventricle

Right ventricle

Systemic circuit

Birds and mammals have four-chambered hearts. Their pulmonary and systemic circuits are totally separate.

Birds and mammals have four-chambered hearts. Their pulmonary and systemic circuits are totally separate.

Pulmonary circuit

Left ventricle

Right ventricle

Systemic circuit

The tissues of birds and mammals have high nutrient demands and thus a very high density of the smallest vessels, the capillaries. Many small vessels present high resistance to the flow of blood. Therefore, high pressure is required in the systemic circuits of birds and mammals. Their pulmonary circuits have fewer capillaries, and thus lower resistance, than their systemic circuits, so the pulmonary circuits of birds and mammals can function at lower pressures.

Vessels shown in red bring oxygenated blood from the lungs to the left heart, which pumps it to the rest of the body.

Vessels shown in red bring oxygenated blood from the lungs to the left heart, which pumps it to the rest of the body.

Spleen Liver

Mammal Systemic Circuit

Vessels shown in blue bring deoxygenated blood from the body to the right heart, which pumps it to the lungs for oxygenation.

Spleen Liver

Was this article helpful?

0 0
Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Responses

  • Terttu
    Do chickens have a systemic circuit of blood flow?
    8 years ago
  • linda
    Do birds have systemic and pulmonary?
    8 years ago
  • Eden
    Do pigeons have a pulmonary circuit?
    7 years ago
  • Emma Marino
    Is the pulmonary circuit completely separate from the systemic circuits?
    6 years ago
  • lelia
    Is pulmonary and systemic blood separated in birds and reptiles?
    6 years ago
  • christina zimmermann
    Do chickens have both a pulmonary circuit and a systemic circuit of blood flow?
    6 years ago
  • shukornia
    Do birds have separate pulmonary and systemic blood circulation birds?
    5 years ago
  • Petra
    What does the pulmonary circuit do in the bird?
    5 years ago
  • rudigar goodbody
    Do mamals have seperate pulmonary and systematic circuts?
    4 years ago
  • phyllis
    Are mammals systematic and pulmonary circulations separate?
    4 years ago
  • MIIKKA GROOP
    Why birds have right systemic artery?
    2 years ago

Post a comment