Anotomy of root and stem
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The document summarizes the key tissues and organs in plants. It describes the three main tissue types - dermal, vascular and ground tissues. It also outlines the three main plant organs - roots, stems and leaves. Roots function to absorb water and nutrients, stems transport fluids and provide structure, and leaves perform photosynthesis.
Anotomy of root and stem
- 3. The three organs of a plant are the roots, stems and leaves The three tissue systems of a plant are dermal tissue, vascular tissue, and ground tissue A special type of tissue called meristematic tissue is the only plant tissue that can produce new cells by mitosis ◦ Found in the tips of shoots and roots
- 4. The outer covering of a plant Consists of a single layer of epidermal cells Cuticle – a waxy layer that often covers the epidermis ◦ Provides protection against water loss & injury May include specialized structures such as root hairs and guard cells
- 5. Transports water and nutrients throughout the plant Xylem – transports water; composed of dead cells Phloem – transports nutrients; composed of living cells called sieve tube elements
- 6. Lies between the dermal and vascular tissues Parenchyma – has thin cell walls and large central vacuoles Collenchyma – has strong, flexible cell walls and is found in larger plants Sclerenchyma – has extremely thick, rigid cells walls
- 7. Types of roots: ◦ Taproot - A thick primary root that grows long and is found mainly in dicots ◦ Fibrous roots – branch extensively and are found mainly in monocots
- 8. Root hairs – tiny projections from the epidermis that increases the surface area for absorption of water Cortex – layer of ground tissue Endodermis – layer of tissue that encloses the vascular tissue Root cap – protects the root as it forces its way through the soil
- 10. Anchor a plant in the ground Absorb water and dissolved nutrients from the soil
- 11. Above-ground organs (usually) Support leaves and fruits Conduct water and sugars throughout plant (xylem and phloem) STEMS
- 12. Three important functions: ◦ Produce leaves, branches and flowers ◦ Hold leaves up in the sunlight ◦ Transport substances between roots and leaves
- 13. Two types: ◦ Monocot – has vascular bundles that contain the xylem & phloem scattered randomly ◦ Dicot – have vascular bundles organized in a ringlike pattern
- 15. Nodes – where leaves are attached Internodes – regions between the nodes Buds – contain undeveloped tissue that can produce new stems and leaves