For a question in a science test that asks What is a circulatory system if the kid answers how deoxygenated blood enters the heart and is pumped through the pulmanory Arteries to the lungs and the oxygenated blood comes from lungs through the Pulmonary veins into the heart and pumped to the rest of the body. Is this answer totally wrong or will the kids atleast 50% correct.
A circulatory system may be open as in Arthropods or closed as in humans. Does the question ask about a specific circulatory system? Your answer would be correct if describing the human circulatory system. Were you supposed to mention the Vena Cava which returns deoxygenated blood to the right atrium? Then, through the valves to the right ventricle? Then, to the pulmonary arteries and on to the lungs? Your answer is fine, however, the question seems a little bit open to interpretation.
What you have is correct. Depending on what level course you're doing, you would have more detail. What chambers of the heart do what part (deox. blood enters right atrium, then right ventricle; pumped to lungs. Returns to left atrium, left ventricle, pumped through aorta to rest of body), etc. Talk about various vessels (arteries, arterioles, capillaries, venules, veins, vena cava) Kidney filtration. You can get into a LOT of detail.