At the small intestines, glucose OS reabsorbed into the Bloodstream via diffusion. The blood travels back to the heart, where it gets pumped back to the lungs.

Length of the answer depends on the marks allocated. Note for the O-level syllabus, glucose is mainly absorbed by active transport (pure Biology) or by diffusion (Science Biology) through the villi in the ileum. If 3 or more marks, you should name all blood vessels that glucose uses to get to the lungs.