BI226 Lecture Notes - Lecture 4: Growth Medium, Endodermis, Phloem
Document Summary
Ryegrass (lolium perenne) root used in all lawns. Little grass that if you could let it flower 30 cm tall (if you didn"t cut your lawn) In 0. 54m3 soil 15,000,000 individual roots totalling 644. 13,000,000,000 root hairs with an absorbent surface the size of a football field. Ejido cave roots at over 50m depth and kaumana cave, hawaii. Roots penetrate dozens of meters down through rocks. Note: all communication and signaling takes place in soil. The good thing about roots: they prevent erosion. No plants, soil will be washed away immediately. The bad thing about roots (from our selfish point of view) Foundation of house (tree planted too close to house can break foundation no problem) First root is root that comes from the embryo. Radicle is embryo root first organ that comes out of seed when it germinates. 2 examples, one of wheat and one of tomatoes (see below)
