If you wanted to speak of the lungs, you would be mentioning the pulmonary circulation, which connects it to the heart for replenishing oxygen, in your words. If you wanted to include them, call them pulmonary arteries or veins, and mention them as separate from the arteries and veins that are visible under skin.
no subject
Half correct-- the answer is the heart.
If you wanted to speak of the lungs, you would be mentioning the pulmonary circulation, which connects it to the heart for replenishing oxygen, in your words. If you wanted to include them, call them pulmonary arteries or veins, and mention them as separate from the arteries and veins that are visible under skin.