Question: Which tissue helps in the secondary growth of the plant?
Answer:
- Vascular cambium is responsible for secondary growth in plants.
- It is a type of lateral meristem.
- The vascular cambium is a thin layer of cells located between the xylem and phloem in the stems and roots of woody plants.
- The primary function of the vascular cambium is to produce secondary vascular tissue.
- The activity of the vascular cambium results in an increase in the girth of the plant stem or root over time. This process is known as secondary growth and is responsible for the formation of annual rings in tree trunks.
| Vascular Cambium | |
| Types | · Fascicular Cambium found in the primary vascular bundles of dicot stems
· Interfascicular Cambium develops between the primary vascular bundles in dicot stems. Also known as the cambium of the pith rays or interfascicular cambium. |
| Role | · Responsible for secondary growth in plants, · Leading to an increase in girth or thickness of stems and roots. · Produces secondary xylem (wood) and secondary phloem. |
| Origin | · Lateral meristem derived from undifferentiated cells located between the primary xylem and primary phloem in the stem and root of woody plants. |
| Cell Division | · The cells actively divide through mitosis resulting in the production of new cells. |
| Differentiation | · The newly formed cells differentiate into secondary xylem (towards the inside)
· Secondary phloem (towards the outside) |
| Annual Rings | · The growth of the vascular cambium results in the formation of annual rings in the wood of trees
· Annual rings can provide information about the age and growth history of the plant. |
| Secondary Xylem | · Cells produced towards the inside of the cambium differentiate into secondary xylem,
· It provides structural support and conducting water and minerals throughout the plant. |
| Secondary Phloem | · Cells produced towards the outside of the cambium differentiate into secondary phloem.
· It is responsible for transporting sugars and organic compounds produced during photosynthesis. |
| Importance for Trees | · Enables trees to increase their diameter
· Helps to sustain their upright growth · Provides support · Water transport and storage capacity |
| Importance for Humans | · Secondary growth of the vascular cambium in woody plants allows for the production of timber
· Wood-based products · Biomass resources that humans utilize for various purposes |