Difference Between Oxygenated and Deoxygenated Blood

Main Difference – Oxygenated vs Deoxygenated Blood

Blood is the main circulatory fluid in animals with a closed circulation system. It circulates through the heart and blood vessels. The two main types of blood vessels are arteries and veins. The main function of blood in the body is to transport oxygen and nutrients to the metabolizing tissues of the body. The heart is the muscular pump that pumps oxygenated blood to the metabolizing tissues while the deoxygenated blood returns to the heart through veins. On that account, oxygenated blood and deoxygenated blood are the two types of blood circulated throughout the body. The main difference between oxygenated blood and deoxygenated blood is that oxygenated blood is composed of more oxygen whereas deoxygenated blood is composed of less oxygen.

Key Areas Covered

1. What is Oxygenated Blood
     – Definition, Facts, Role
2. What is Deoxygenated Blood
     – Definition, Facts, Role
3. What are the Similarities Between Oxygenated and Deoxygenated Blood
     – Outline of Common Features
4. What is the Difference Between Oxygenated and Deoxygenated Blood
     – Comparison of Key Differences

Key Terms: Arterial Blood, Arteries, Carbon Dioxide, Deoxygenated Blood, Oxygen, Oxygenated Blood, Veins, Venous Blood

What is Oxygenated Blood

Oxygenated blood refers to the blood that has been exposed to oxygen in the lungs. It is also known as arterial blood. The blood flows to the lungs to take up atmospheric oxygen by hemoglobin in the red blood cells. It flows to the left chamber of the heart from the lungs through the pulmonary vein. Since the majority of hemoglobins in this blood are bound to oxygen, the oxygenated blood is bright red in color. It exhibits a purple color through the skin. The partial pressure of oxygen in the oxygenated blood is about 100 mmHg. The oxygenated blood is rich in oxygen as well as other nutrients such as glucose, amino acids, and vitamins. It flows from the heart to the metabolizing tissues throughout the body to supply oxygen and nutrients to the cells. Oxygenated blood flows through the systemic arteries in the body. The oxygenated and deoxygenated blood drops are shown in figure 1.

Figure 1: Oxygenated (left) and Deoxygenated (right) Blood

Oxygenated or arterial blood is mainly used to measure the acidity (pH), oxygen concentration, and carbon dioxide concentration in the blood. This test method is called the arterial blood gas (ABG) test. It is used to check the efficiency of the lungs to remove carbon dioxide from the blood as well as to take oxygen into the blood.

What is Deoxygenated Blood

Deoxygenated blood refers to the blood that has a low oxygen saturation when compared to the blood leaving the lungs. It is also known as venous blood. The tissues of the body take up oxygen from the oxygenated blood and return carbon dioxide as a metabolic waste. Thus, the blood that flows out from the tissues consists of a low partial pressure of oxygen and high partial pressure of carbon dioxide. This blood flows through the systemic vein to the right atrium of the heart. It flows to the lungs from the right ventricle to the lungs through the pulmonary artery. Deoxygenated blood consists of fewer amounts of nutrients when compared to oxygenated blood. On the contrary, it is rich in metabolic wastes such as urea in addition to carbon dioxide. The flow of both oxygenated and deoxygenated blood throughout the body is shown in figure 2.

Figure 2: Oxygenated and Deoxygenated Blood Flow

The deoxygenated blood in veins is used in routine blood tests. It can be collected by the direct puncture of a vein by a veinpuncture.

Similarities Between Oxygenated and Deoxygenated Blood

• Oxygenated and deoxygenated blood are the two main types of blood circulated throughout the body.
• Both oxygenated and deoxygenated blood flow through the blood vessels.
• Both oxygenated and deoxygenated blood consist of similar osmolarities, hemoglobin level, and salinity.

Difference Between Oxygenated and Deoxygenated Blood

Definition

Oxygenated Blood: Oxygenated blood refers to the blood that has been exposed to oxygen in the lungs.

Deoxygenated Blood: Deoxygenated blood refers to the blood that has a low oxygen saturation relative to blood leaving the lungs.

Alternative Names

Oxygenated Blood: The oxygenated blood is also called arterial blood.

Deoxygenated Blood: The deoxygenated blood is also called venous blood.

Oxygen Concentration

Oxygenated Blood: The oxygen concentration of oxygenated blood is high.

Deoxygenated Blood: The oxygen concentration of deoxygenated blood is low.

Carbon Dioxide Concentration

Oxygenated Blood: The carbon dioxide concentration of oxygenated blood is low.

Deoxygenated Blood: The carbon dioxide concentration of deoxygenated blood is high.

Blood Color

Oxygenated Blood: The oxygenated blood is bright red in color.

Deoxygenated Blood: The deoxygenated blood is blackish red in color.

Blood Flow

Oxygenated Blood: The oxygenated blood flows from the lungs through the left chambers of the heart to the metabolizing tissues of the body.

Deoxygenated Blood: The deoxygenated blood flows from the metabolizing tissues of the body through the right chambers of the heart to the lungs.

Direction of the Blood 

Oxygenated Blood: Oxygenated blood flows away from the heart.

Deoxygenated Blood: Deoxygenated blood flows towards the heart.

Blood Vessels

Oxygenated Blood: Oxygenated blood flows through the pulmonary vein and systemic arteries.

Deoxygenated Blood: Deoxygenated blood flows through the pulmonary artery and systemic vein.

Driving Force

Oxygenated Blood: The driving force of the oxygenated blood is the pumping pressure of the heart.

Deoxygenated Blood: The driving force of the deoxygenated blood is the muscular contractions.

Blood Pressure

Oxygenated Blood: The regular pressure of the oxygenated blood is 120/80 mm Hg.

Deoxygenated Blood: The regular pressure of the deoxygenated blood is 5-8 mm Hg at the atrium.

Content

Oxygenated Blood: The oxygenated blood is rich in oxygen and nutrients such as glucose, amino acids, and vitamins.

Deoxygenated Blood: The deoxygenated blood is rich in HCO3 and metabolic wastes such as urea.

Blood pH

Oxygenated Blood: The pH of the oxygenated blood is 7.40.

Deoxygenated Blood: The deoxygenated blood has a lower pH than the oxygenated blood.

Temperature

Oxygenated Blood: The temperature of the oxygenated blood is 37 ºC.

Deoxygenated Blood: The temperature of the deoxygenated blood is lower than that of the venous blood.

Role

Oxygenated Blood: The main function of oxygenated blood is to supply oxygen to the metabolizing tissues.

Deoxygenated Blood: The main function of deoxygenated blood is to carry carbon dioxide to the lungs.

Conclusion

Oxygenated and deoxygenated blood are the two types of blood found as the main circulatory fluid of the body in animals with a closed circulatory system. Oxygenated blood consists of a high partial pressure of oxygen to supply oxygen to the metabolizing tissues. On the other hand, deoxygenated blood consists of a low partial pressure of oxygen. The main difference between oxygenated and deoxygenated blood is the amount of oxygen carried by each type of blood.

Reference:

1. “Systemic Circulation – National Library of Medicine – PubMed Health.” National Center for Biotechnology Information, U.S. National Library of Medicine, Available here.

Image Courtesy:

1. “Oxygenated vs deoxygenated RBC” By Rogeriopfm – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “2101 Blood Flow Through the Heart” By OpenStax College – Anatomy & Physiology, Connexions Web site, Jun 19, 2013 (CC BY 3.0) via Commons Wikimedia