Structure of the Circulatory System

 

Structure of the Circulatory System

Miss Angler

The Circulatory System

Welcome back! Today we will be looking at the structure of the circulatory system. It's important to understand how our circulatory system is structured so that we can understand how it functions. There are two types of circulatory systems: open and closed. Open circulatory systems, like those found in insects, have blood vessels that are open at the ends, allowing blood to leak out into the tissues. Closed circulatory systems, like those found in humans, have blood vessels that keep the blood contained within them, allowing for a more specialized and efficient system.

Double Circulatory System

Humans have a closed and double circulatory system. This means that the heart pumps blood twice around the body, with slightly different destinations each time. The first circulation is called systemic circulation, where oxygenated blood is delivered to the body tissues. The second circulation is called pulmonary circulation, where deoxygenated blood is reoxygenated in the lungs. This double circulatory system allows for efficient oxygen delivery and waste removal.

Components of the Circulatory System

Now let's familiarize ourselves with the structure of the circulatory system. We will focus on the external and internal structures of the heart. It's important to know these structures for tests and exams. The external structure of the heart is different from its internal structure, so it's important to understand both. Some structures may be clearer in textbooks than in real life, so let's go through the labels.

External Structures

• Superior vena cava: The largest vein that enters the heart.

• Right atrium: The top chamber of the heart where blood is received from the vena cava.

• Coronary arteries: Arteries specifically for the heart to provide it with oxygen and energy.

Internal Structures

(Internal structures will be covered in the next video)

Understanding the Anatomy of the Heart

In this article, we will explore the different components of the heart and their functions. It is important to have a clear understanding of the heart's anatomy to comprehend how it works.

Arteries and Coronary

• The arteries are responsible for keeping the heart alive.

• Coronary refers to the heart, so when we mention coronary, we are referring to the heart.

• Coronary arteries supply the heart with its own nutrients.

The Right Ventricle

The right ventricle is the lower and muscular part of the heart.

The Right Atrium

• The right atrium is located on the outside of the heart.

• It is softer and less muscular compared to the right ventricle.

• The right ventricle is thick and muscular as it pushes blood out of the heart and into the lungs.

The Aorta

The aorta is the largest blood vessel in the body.

The Pulmonary Artery

The pulmonary artery carries blood from the heart to the lungs.

The Pericardium

The pericardium is a thin membranous layer that protects the heart against friction.

The Left Atrium

The left atrium is situated on top of the heart.

It fills with blood before it enters the ventricles.

Coronary Arteries

Coronary arteries supply the heart with its own blood vessels and nutrients.

The Left Ventricle

The left ventricle is the thickest and most muscular ventricle.

It pushes blood against gravity to different parts of the body.

The Apex of the Heart

The apex is the pointy tip of the heart.

Internal Structure of the Heart

Let's now delve into the internal structure of the heart.

Some key structures include:

• The superior vena cava, which carries blood from the top of the body.

• The right pulmonary artery, which carries blood to the lungs.

• The pulmonary valve, which prevents backflow of blood into the heart.

• The pulmonary veins, which bring blood from the lungs back to the heart.

• The right atrium, where blood first flows into.

• The tricuspid valve, which allows blood to flow from the right atrium to the right ventricle.

• The inferior vena cava, which carries blood from the lower half of the body.

• Papillary muscles, which help open and close the valves.

Other Important Blood Vessels

Other significant blood vessels include the carotid artery, subclavian artery, and the aortic arch.

The carotid artery is located in the neck, while the subclavian artery runs under the collarbone.

The aortic arch is the large arching blood vessel that carries blood from the heart to the rest of the body.

Conclusion

Understanding the anatomy of the heart is essential to comprehend its functions and how it keeps our bodies alive and healthy.