Chapter 35 - Roots and Mineral Nutrition

Chapter 35 - Roots and Mineral Nutrition - James Truong...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
James Truong 1 Chapter 35 – Roots and Mineral Nutrition Roots are for anchoring, absorption, storage, and synthesize hormones Taproot system o Has one main root formed from the radical (embryonic root) from which many lateral roots extend o Good for storage and eating Carrots and other underground vegetables Fibrous Root System o Has many adventitious (come from the stem) roots of same size, developing from end of stem o Lateral roots branch from adventitious roots o Original radical in fibrous died; fibrous roots come off of stem o More surface area, anchoring and absorbing nutrients Root system is about the same size as the shoot system Primary roots – original root, goes straight down o Tissues Epidermis – single layer of root Ground tissues (cortex, pith) Vascular tissues (xylem and phloem) Monocot: vascular bundles are in a circle o Spaced so that water can get through them Dicot – xylem is in a star, phloem surrounds the star Structures o Root cap Protective layer that covers the root tip Covers delicate root apical meristem May orient so that it grows downward Secretes sugar that provides lubrication o Epidermis – protects the root o Root hairs – short-lived extensions of epidermal cells help absorb water (get from ppt) o Cortex – parenchyma cells, often store starch Amyloplasts – organelles that store starch o Endodermis (not dermal tissue, actually ground tissue) – single layer of rectangular cells Innermost layer of cortex (separate the cortex from the vasculature) Regulates movement of water and minerals into root xylem Casparian strip – rubber band thing that keeps water and dissolved minerals out Subarin – keeps the water out
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/02/2009 for the course SCI 90210 taught by Professor Durkka during the Spring '09 term at École Normale Supérieure.

Page1 / 4

Chapter 35 - Roots and Mineral Nutrition - James Truong...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online