Which condition is necessary for enzymes to function properly in the human body

Number and variety of living organisms includes genetic, species, and ecological types

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?

Does any one know what blood tastes like