Karthikeyan

The circulatory system carries blood all around the body.

• The heart pumps blood.

• Arteries take oxygen-rich blood from the heart to the body.

• Veins bring oxygen-poor blood back to the heart.

• Capillaries are tiny tubes where oxygen and nutrients go into cells, and waste like carbon dioxide comes out.

There are two pathways:

1. Pulmonary circulation → heart → lungs → heart (for oxygen).

2. Systemic circulation → heart → body → heart (to deliver oxygen & nutrients).