Cork cambium

Definition

Cork cambium is a type of lateral meristematic tissue responsible for producing cork cells, which form the outer protective layer of stems and roots in woody plants. This tissue plays a vital role in secondary growth by facilitating the development of the periderm, which replaces the epidermis as the plant matures and increases in girth.

5 Must Know Facts For Your Next Test

1. Cork cambium originates from the outer layers of the stem and is crucial for forming the periderm as plants undergo secondary growth.
2. The cells produced by cork cambium are dead at maturity and serve as a barrier to protect against physical damage and pathogen invasion.
3. Cork cambium functions continuously throughout a plant's life, enabling ongoing production of new cork cells as older layers are sloughed off.
4. The cork cells contain suberin, a waxy substance that enhances their impermeability to water and gases, providing insulation for the plant.
5. Cork cambium is often referred to as phellogen because it generates cork (phellem) and phelloderm, which is a layer of living cells underneath the cork.

Review Questions

• How does cork cambium contribute to the overall process of secondary growth in woody plants?
  • Cork cambium contributes to secondary growth by producing cork cells that form the periderm, replacing the epidermis as the plant matures. This allows for an increase in stem thickness while providing protection against environmental stressors. As it continues to produce new layers of cork, it helps maintain the structural integrity of the plant over time.
• Discuss the significance of suberin in the cells produced by cork cambium and its impact on plant health.
  • Suberin is a key component of cork cells produced by cork cambium, providing waterproofing and resistance to pathogen invasion. This waxy substance not only protects against dehydration but also serves as a barrier against harmful microorganisms. The presence of suberin enhances the overall resilience of woody plants, ensuring their survival in various environmental conditions.
• Evaluate how disruptions in cork cambium activity might affect a plant's development and survival in its environment.
  • Disruptions in cork cambium activity can severely impact a plant's ability to grow and survive. If cork cambium does not function properly, a plant may struggle to produce adequate protective tissues, leaving it vulnerable to pests, diseases, and physical damage. Furthermore, impaired formation of the periderm can lead to water loss and reduced efficiency in gas exchange, ultimately compromising the plant's health and growth potential.

Related terms

Periderm: The protective tissue that replaces the epidermis in woody plants, composed of cork, cork cambium, and phelloderm.

Lateral Meristem: Meristematic tissue located along the sides of stems and roots that is responsible for secondary growth, allowing plants to increase in diameter.

Secondary Growth: The process by which plants increase in thickness or girth through the activity of lateral meristems, primarily cork cambium and vascular cambium.