BIOL 172 Lecture Notes - Lecture 11: Stoma, Topsoil, Cuticle
Document Summary
Also performs transpiration (loss of water) in stomata. Doesn"t take place in the upper epidermis of leaves. Occurs in mesophyll b/c uv rays would damage it if it were in epidermis. Cuticle and stomata: gas exchange and water transport. Also occur on stems of plants during primary growth. Don"t occur in the roots during primary growth b/c sun can"t reach it, preventing its facilitation. Element absorption by plant roots: minerals are dissolved in water and absorbed by roots in form of ions. Except c, o, and h; adsorbed by monosaccharides via glucose and other processes. Cations: bind to soil and not easily leached. Makes it more difficult for them to be absorbed by the roots of plants. Not a problem with anions b/c they don"t bind to soil and are easily leached. Topsoil: most fragile part of the plant ecosystem. Overuse can deplete soil minerals, leading to soil erosion.
