BIO 2137 Lecture Notes - Lecture 13: Casparian Strip, Xylem, Root Pressure
25 Nov 2016
School
Department
Course
Professor
Document Summary
Inorganic nutrients in a solution = ionic form. Water and solutes are mostly absorbed from root system. All nutrients entering plant are dissolved in water. Solution moves from soil to epidermis and cortex and then into xylem. Cell with selectively permeable membranes to control which solutes go into xylem. Lots of protons, displaces other positive ions in soil. Need co2 from outside and need to get ride of o on the inside. "cohesion-adhesion-tension" mechanism in water in xylem from roots to leaves. Polar molecule = cohesion, water spiders standing on water. Adhesion = meniscus, water is gluing itself to stuff. Tension = pulling the water up in the tube. Water loss creates a gradient in solute concentration in leaf cells, which makes water move. When water leaves in stomata (diffusion), water from cells move, those cell solute concentration increases, the next cells move their water (osmosis), etc.
