Why cell called the functional and structural unit of life?​

Ivan is looking at a cross section of a stem taken from a vascular plant. he sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. how do these two structures work together in a living plant?

Why do mountaineers become breathless as they reach high altitudes

Which is abiotic? a. tree sap b. insect c. sunlight d. wood table