Lateral Meristem
Located laterally, responsible for increase in plant girth (secondary growth), includes vascular and cork cambium.
What is Lateral Meristem?
The increase in the diameter or girth of plant organs, primarily in stems and roots, due to the activity of lateral meristems.
Key points
- Define lateral meristems and their function.
- Identify the two main types of lateral meristems.
- Explain the role of vascular cambium in secondary growth.
- Explain the role of cork cambium in forming the periderm.
Common exam trap
Confusing lateral meristems with apical meristems.
Definitions
- Term
Secondary Growth
- Meaning
The increase in the diameter or girth of plant organs, primarily in stems and roots, due to the activity of lateral meristems.
- Term
Vascular Cambium
- Meaning
A lateral meristematic tissue located between the xylem and phloem that produces secondary xylem and secondary phloem.
- Term
Cork Cambium (Phellogen)
- Meaning
A lateral meristematic tissue that arises in the cortex or epidermis and produces cork (phellem) and secondary cortex (phelloderm).
- Term
Periderm
- Meaning
The protective outer layer of stems and roots of woody plants, consisting of cork cambium, cork, and secondary cortex.
- Term
Secondary Xylem
- Meaning
Wood, produced by the vascular cambium towards the inside.
- Term
Secondary Phloem
- Meaning
Produced by the vascular cambium towards the outside, forming part of the bark.
- Term
Cork (Phellem)
- Meaning
Dead cells with suberized walls, produced by the cork cambium towards the outside, providing protection.
- Term
Secondary Cortex (Phelloderm)
- Meaning
Tissue produced by the cork cambium towards the inside.
Learning objectives
Define lateral meristems and their function.
Identify the two main types of lateral meristems.
Explain the role of vascular cambium in secondary growth.
Explain the role of cork cambium in forming the periderm.
Differentiate between primary and secondary growth.
Prerequisites
Plant Tissues (Apical Meristem, Permanent Tissues)
Types of Growth (Primary and Secondary)
Anatomy of Monocot and Dicot Stems and Roots
Common mistakes
Confusing lateral meristems with apical meristems.
Not distinguishing between the roles of vascular cambium and cork cambium.
Forgetting that lateral meristems are responsible for girth increase, not length increase.
Assuming secondary growth occurs in all plants.
Keywords
Lateral Meristem
Secondary Growth
Vascular Cambium
Cork Cambium
Periderm
Secondary Xylem
Secondary Phloem
Girth Increase
Wood
Bark
Phellem
Phelloderm
Phellogen
Practice preview
The vascular cambium is a meristematic tissue responsible for secondary growth. Its activity results in:…
medium
Cork cambium is a type of lateral meristem that produces:…
medium
The increase in girth of a plant stem is primarily due to the activity of:…
easy