Definition

1. Noun:
   • A unit strand of the vascular system in stems and leaves of higher plants consisting essentially of xylem and phloem: A "vascular bundle" is a discrete, elongated structure within a plant that contains the primary tissues responsible for transporting fluids and nutrients. It is the fundamental unit of the plant's vascular system, typically composed of xylem (for water and mineral transport) and phloem (for sugar and nutrient transport), often bundled together with supporting tissues.

Usage Examples

• Noun:
  • In a cross-section of a stem, you can clearly see the ring of vascular bundles.
  • The arrangement of vascular bundles differs between monocot and dicot plants.
  • Damage to a major vascular bundle can hinder the plant's ability to transport water.

Advanced Usage

• "Closed vascular bundle": A type of bundle where the cambium (a layer of growth tissue) is absent, preventing secondary growth. Common in monocot plants.

  • Grasses typically have closed vascular bundles.

• "Open vascular bundle": A type of bundle that contains cambium, allowing for secondary growth (increase in girth). Common in dicot plants.

  • The open vascular bundles in trees contribute to the formation of wood.

• "Radial vascular bundle": An arrangement where xylem and phloem are situated on different radii, as seen in plant roots.

  • The root's radial vascular bundle arrangement facilitates efficient transport from the soil.

Variants and Related Words

• Vascular tissue (n): The collective term for the transporting tissues in plants, primarily xylem and phloem.

  • The plant's vascular tissue is crucial for its survival.

• Stele (n): The central core of vascular tissue in roots and stems.

  • The stele is comprised of the vascular bundles and associated tissues.

• Fibrovascular bundle (n): An older or more descriptive term sometimes used synonymously with "vascular bundle," emphasizing the presence of fibrous strengthening tissues.

  • The leaf's strength comes from its network of fibrovascular bundles.

Synonyms

• Vascular strand: A direct synonym emphasizing the elongated, cord-like structure.
• Vein (in leaves): In the context of leaves, the visible vascular bundles are commonly called veins.
• Fascicle (in botany): Can refer to a small bundle or cluster, sometimes used for vascular bundles.

Related Phrases and Terms

• Bundle sheath (n): A layer of cells, often thick-walled, surrounding a vascular bundle.

  • The bundle sheath helps regulate the flow of materials into and out of the vascular bundle.

• Vascular cambium (n): A layer of meristematic cells found in open vascular bundles, responsible for producing secondary xylem and phloem.

  • The vascular cambium is active in the open vascular bundles of perennial plants.

• Vascular cylinder (n): Refers to the entire central vascular structure in a root or stem, which is made up of multiple vascular bundles.

  • The vascular cylinder is clearly visible under the microscope.

Noun

1. a unit strand of the vascular system in stems and leaves of higher plants consisting essentially of xylem and phloem