Select the correct answers to the questions from the given options. (Do not copy the questions, write the correct answer only.)
Which is the correct sequence of blood flow in the Pulmonary and Systemic Circulation?
Topic: Double circulation — sequence of blood flow
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
(a) Right Atrium → Right Ventricle → Lungs → Left Atrium → Left Ventricle → Body tissues.
Follow one drop of deoxygenated blood returning from the body: it enters the RIGHT ATRIUM from the venae cavae passes through the tricuspid valve into the RIGHT VENTRICLE is pumped through the pulmonary artery to the LUNGS, where it is oxygenated — this is PULMONARY circulation returns by the pulmonary veins to the LEFT ATRIUM passes through the bicuspid valve into the LEFT VENTRICLE is pumped through the aorta to the BODY TISSUES — this is SYSTEMIC circulation
TWO RULES that let you eliminate wrong options instantly:
blood always flows ATRIUM → VENTRICLE within the same side, never the reverse. Options (B) and (C) begin "Left Ventricle → Left Atrium" and can be struck out on sight.
the RIGHT side always goes to the LUNGS and the LEFT side always to the BODY. Option (D) sends the right ventricle to the body tissues, so it goes too.
That leaves (A) without any need to trace the full circuit.
This arrangement is called DOUBLE CIRCULATION because the blood passes through the heart TWICE in one complete circuit of the body.
Right Atrium → Right Ventricle → Lungs → Left Atrium → Left Ventricle → Body tissues.