1. Arteries – Carry blood away from the heart under high pressure.

2. Arterioles – Small branches of arteries that control blood flow into capillaries.

3. Capillaries – Tiny vessels where exchange of gases, nutrients, and waste occurs.

4. Venules – Small vessels that collect blood from capillaries and lead to veins.

5. Veins – Carry blood back to the heart, often with valves to prevent backflow.

1. Interatrial septum – Divides the left and right atria.

2. Interventricular septum – Divides the left and right ventricles.

   
   

Layers of the Heart Wall:

1. Endocardium – Inner layer; lines the heart chambers and valves.

2. Myocardium – Middle, muscular layer; responsible for heart contractions.

3. Epicardium – Outer layer; part of the pericardium that protects the heart.