How many atria are present in a human heart?

The correct answer is two because the human heart consists of four chambers in total: two atria and two ventricles. The atria are the upper chambers of the heart, specifically designed to receive blood coming into the heart. The right atrium receives deoxygenated blood from the body through the superior and inferior vena cavae, while the left atrium receives oxygenated blood from the lungs through the pulmonary veins. This arrangement is crucial as it facilitates the efficient flow of blood through the heart and into the lungs or the rest of the body. The presence of two atria allows the heart to effectively manage the different types of blood it encounters, supporting overall circulatory function.