Botany

• Roots - cylindrical structures which generally grow downward into the soil
• Roots - Underground extension of the plant axis
• Function of Roots:

  Anchoring the plant firmly to a substrate

  Absorbing water and minerals

  Produce hormone

  Food storage

  Asexual reproductive organ
• Seed contains a young plant (embryo)
• origin and structure of the roots

  Radicle or Rudimentary root – it is the first structure that appears when seed germinates

  Primary root – it is the first root (developed from radicle)

  Secondary root – branches of the primary root

  Tertiary root – branches of the secondary root
• External Structure of the Roots:

  Organization of Root Systems - Composed of the primary root and its branches
• Taproot System

  • Common in dicots and conifers

  • Develop from the embryonic root or radicle that enlarges •

  Consists of one main root with smaller branched or lateral roots grow.

  This persists throughout the life duration of the plant

  • Examples •Carrot, Sugar Beet, Radish, Lateral roots that develop from taproot Sweet potato/camote, Cassava
• Fibrous or Diffuse Root System

  Common in monocots

  Consists of numerous fine roots similar in diameter

  – Not derived from the primary root but composed of slender individual roots that are alike in size

  – Arises due to the radicle that dies during or immediately after germination

  – Example (cereals, bulbs and grasses) • Corn , Talahib, Yard grass, Onion
• Adventitious Root System

  Roots that develop from other parts of the plant

  Increase the absorptive and transport capacity of the root system – Types:

  Prop root – arise from the stem – Balete Tree

  Brace roots – used for support – Corn Plant

  Clinging or Climbing roots – arise from the nodes – Orchids