Cardiovascular System Overview

The Cardiovascular System

• The circulatory system, composed of the heart and blood vessels, is vital for maintaining the body's internal environment (interstitial fluid) and ensuring optimal cellular function.
• It delivers nutrients and removes waste products.
• The circulatory system can be functionally divided into: left ventricle, arteries, arterioles, capillaries, venules and veins, right ventricle, pulmonary vessels, and lymphatic vessels.

The Left Ventricle

• Acts as a high-pressure pump, delivering oxygenated blood to the body's systemic circulation at 100-140 mmHg pressure.

Arteries

• Contain elastic fibers allowing them to stretch during ventricular contraction (systole) to accommodate blood flow.
• Recoil during ventricular relaxation (diastole) helps maintain blood flow to organs.

Arterioles

• Thick smooth muscle layer allows for diameter adjustment.
• Main sites of resistance to blood flow.
• Regulate blood flow to tissues and arterial blood pressure by changing diameter.

Capillaries

• Sites of nutrient and waste exchange.
• Thin walls allow efficient exchange.
• Offer a large cross-sectional area for increased exchange rates.

Venules and Veins

• Collect blood from capillaries and return it to the heart.
• Systemic veins have large capacity and are very distensible, accommodating large volumes of blood.

Right Ventricle

• Low-pressure pump, pumping the same volume as the left ventricle but at lower pressure (20-30 mmHg).
• Pumps blood to the pulmonary circulation.

Pulmonary Vessels

• Vital for gas exchange.

Lymphatic Vessels

• An accessory system running parallel to veins.
• Collects excess extracellular fluid and returns it to the venous system via lymphatic ducts.

Important Notes:

• All arteries carry oxygenated blood except for the pulmonary artery.
• All veins carry deoxygenated blood except for the pulmonary veins.

Explore the complexities of the cardiovascular system, focusing on its vital components like the heart, blood vessels, and their functions. This quiz covers the roles of the left ventricle, arteries, and arterioles in circulation and regulation. Test your knowledge on how these elements work together to maintain homeostasis in the body.