Why membranes are selectively permeable

Has regulatory areas for thirst, hunger, body temperature, water balance, and blood pressure

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?

Slow down transpiration by the stomata question 9 options: a guard cells; closing b chloroplasts; closing c guard cells; opening d chloroplasts; opening