Question

Systemic heart refers to:
(a)The heart that contract under stimulation from the nervous system
(b)Left auricle and left ventricle in higher vertebrates
(c)Entire heart in lower vertebrates
(d)The two ventricles together in humans

Answer 1

Hint: In the process of the systemic circulation, the aorta carries oxygenated blood to all parts of the body, and superior and inferior vena cava brings deoxygenated blood from the entire body and drains into the heart.

Complete step-by-step answer:

Systemic heart refers to the left auricle and left ventricle in higher vertebrates. The systemic circulation distributes nutrients and oxygen to the different parts of the body. The circulatory system of humans (higher vertebrates) is divided into two separate systems of circuits, the systemic circuit, and the pulmonary circuit. Each of these systems consists of a similar sequence of blood vessels. The circulation of oxygenated blood starts from the left auricle followed by the left ventricle. Blood is pumped out of the heart into arterioles through arteries (blood vessels which are muscular tubes lined by smooth tissue) of decreasing size, which merge before reaching the sites of exchange with the capillaries (tiny blood vessels connecting arteries to veins). Blood leaving the capillaries is gathered into venules and then veins before returning to the heart. Also, the left side (left auricle and left ventricle) provides pressure to propel blood to the entire body. Hence in the systemic circulation, these two chambers are involved and are referred to as the systemic heart.
So, the correct answer is 'Left auricle and left ventricle in higher vertebrates'.

Note: The pulmonary circuit, the right side of the heart, carries deoxygenated blood from the heart to the lungs for gas exchange with the atmosphere and returns oxygenated blood to the left atrium and ventricle of the heart. Both systems, i.e systemic circulation, and pulmonary circulation are readily paired and contrasted with each other.