The human heart is located on the left side between the two lungs in the thoracic cavity above the diaphragm. It is triangular in shape and reddish-brown in color. Its broad upward part is called the base and the narrow downward part is called the apex. Adult human heart is 12 cm long and 8 cm wide. Male heart weighs 250-390 grams and female 200-275 grams. A male’s heart is one-third larger than a female’s.