VBDI 4997E: Pre-Veterinary Histology - The Cardiovascular System

A collection of vocabulary terms and their definitions related to the cardiovascular system, as covered in the Pre-Veterinary Histology lecture.

Cardiovascular System

A system that comprises the heart, blood, and lymph vessels, responsible for circulating nutrients, oxygen, and waste products throughout the body.

Aorta

The largest blood vessel in the body that distributes oxygenated blood from the left ventricle to the rest of the body.

Right Atrium

The chamber of the heart that receives unoxygenated blood from the body.

Pulmonary Artery

The blood vessel that carries unoxygenated blood from the right ventricle to the lungs.

Pulmonary Vein

The blood vessel that returns oxygenated blood from the lungs to the left atrium.

Left Ventricle

The chamber of the heart that pumps oxygenated blood into the aorta.

Capillaries

Small blood vessels where nutrient and gas exchange occurs between blood and tissues.

Arteries

Thick-walled blood vessels that carry oxygenated blood away from the heart (except for the pulmonary artery).

Veins

Thinner-walled blood vessels that carry unoxygenated blood back to the heart (except for the pulmonary vein).

Tunica Intima

The innermost layer of blood vessels, composed of a lining epithelium and connective tissue.

Tunica Media

The middle layer of blood vessels, containing smooth muscle cells and elastic fibers.

Tunica Adventitia

The outermost layer of blood vessels, made up of collagen fibers and associated with small nerves and blood vessels.

Elastic Artery

An artery, such as the aorta, characterized by a prominent internal elastic membrane and numerous elastic fibers.

Muscular Artery

An artery that has a thick tunica media primarily composed of smooth muscle cells, such as those that branch from the aorta.

Continuous Capillaries

Capillaries with a smooth wall and no interruptions, allowing for selective permeability.

Fenestrated Capillaries

Capillaries that have small openings (windows) allowing for greater exchange of materials.

Sinusoidal Capillaries

Dilated capillaries with large pores that line the sinuses of organs like the liver and spleen.

AV Valves

Valves located between the atria and ventricles, including the tricuspid and mitral valves, that ensure unidirectional blood flow.

Pericardium

The thick membrane enclosing the heart.

Endocardium

The innermost layer of the heart, composed of endothelium and connective tissue.

Myocardium

The muscular layer of the heart responsible for contraction and pumping blood.

Epicardium

The outer layer of the heart, made of serosal epithelium and connective tissue.

Sinoatrial Node

The heart's natural pacemaker that generates electrical impulses to initiate heartbeats.

Bundle of His

A collection of heart muscle cells that transmit impulses from the AV node to the ventricles.

Purkinje Fibers

Modified cardiac muscle fibers that conduct impulses to the ventricular muscles, facilitating contraction.