The heart is a muscular organ that pumps blood through the body. The heart has four chambers: the left atrium is a chamber on the left side of the heart that receives oxygenated blood from the lungs; the right atrium is a chamber located on the right side of the heart that receives deoxygenated blood from the body; the left ventricle is a chamber on the left side of the heart that pumps oxygenated blood to the body; and the right ventricle is a chamber on the right side of the heart that pumps deoxygenated blood to the lungs.
The blood vessels are tubes that carry blood through the body. There are three different types of blood vessels: arteries, capillaries, and veins. Arteries are blood vessels that carry oxygenated blood away from the heart to the body. Capillaries are tiny blood vessels that allow oxygen and nutrients to pass from the blood to the tissues. Veins are blood vessels that carry deoxygenated blood back to the heart.
The blood is a tissue that contains red blood cells, white blood cells, platelets, and plasma. Red blood cells carry oxygen from the lungs to the body. White blood cells fight infection. Platelets help to stop bleeding. Plasma is the liquid part of blood that contains water, electrolytes, and proteins.
The circulatory system is a complex network of organs and tissues that work together to transport blood, oxygen, and nutrients throughout the body.
