Plant Structure & Function 2 PDF

Content Unit 5: Diversity of life Lesson 2: Plant Structure & Function Or photos Week 9 Block 1 www.ens.sch.a e ...

Content Unit 5: Diversity of life Lesson 2: Plant Structure & Function Or photos Week 9 Block 1 www.ens.sch.a e  MYP Key Elements Title Key Concept / Related Concepts: - Adaptation, Transformation, Biodiversity, Evolution Global Context: - Scientific and Technical Innovation – Exploring the natural world and the processes that lead to biodiversity. Statement of Inquiry: - The evolution of plants over time through adaptation and environmental interactions fosters biodiversity and ecological balance. Inquiry Questions: - Factual: What are the stages of plant evolution? - Conceptual: How do environmental factors influence plant diversity? - Debatable: To what extent should humans intervene in plant evolution to enhance biodiversity?  Learning Targets Explain the structure & function of root. Explain the structure & function of stem. Explain the structure & function of leaves. Key Vocabulary 8. ground tissue Title 1.epidermis 2.xylem 9. root cap 3.vessel element 10. cortex 4.tracheid 11. endodermis 5.phloem 12. petiole 6.sieve tube member 13. Transpiration 7. Companion cell 14. Pericycle Plant Cells Plant cells are identifiable by their Plants have many types of cells cell walls and large central vacuole. adapted for specific purposes. Plant Cells  Parenchyma Cell Functions: 1.Storage 2.Photosynthesis 3.Gas exchange 4.Protection 5.Tissue repair and replacement  Plant Cells  Collenchyma Cell Functions 1. Support for surrounding tissues 2. Provides flexibility for plant 3. Tissue repair and replacement  Plant Cells  Sclerenchyma Cell Functions: 1. Support 2. Transport of materials Plant Cells Plant Tissues  A tissue is a group of cells that work together to perform a function.  A plant tissue can be composed of one or many types of cells.  There are four different tissue types found in plants: 1.Meristematic 2.Dermal 3.Vascular 4.Ground Plant Tissues  Vascular Tissues 1. Xylem is the water-carrying vascular tissue, composed of specialized cells called vessel elements and tracheid. Plant Tissues VASCULAR VESSEL LACK END WALLS, TISSUES ELEMENTS ARE ALLOWING FREE TUBULAR CELLS MOVEMENT OF STACKED END-TO- WATER FROM END. ONE VESSEL ELEMENT TO ANOTHER  Plant Tissues Vascular Tissues Tracheid's are tubular cells with pitted ends and end walls. Less efficient at moving water than vessel elements  Plant Tissues  Vascular Tissues 2. Phloem is the main food-carrying tissue in vascular plants.  Consists of two types of cells: 1. Sieve tube members 2. Companion cells Plant Tissues  Sieve tube members contain cytoplasm but lack nuclei and ribosomes when mature.  Plant Tissues  Companion cells occur next to sieve tube cells and have a nucleus.  Roots  The tip of a root is covered by the root cap.  The root cap consists of parenchyma cells to help protect root tissues as the root grows.  Roots  The layer between the epidermis and vascular tissue is the cortex.  Directly next to the endodermis, toward the center of the root, is the pericycle, which produces lateral roots.  Stems  Structure 1. Herbaceous stems are soft, flexible, and capable of photosynthesis. Asparagus Stems  Structure 2. Woody stems are rigid and fibrous. Trees Shrubs Stems  Main function  Main function is support of leaves and reproductive structures Stems  Types & function of stems: 1. Tuber: food storage Stems  Types & function of stems: 2. Rhizome: food storage, asexual reproduction. Stems  Types & function of stems: 3. Runner: asexual reproduction. Stems  Types & function of stems: 4. Bulb: food storage Stems  Types & function of stems: 5. Corm: food storage  Leaves  Structure:  In most plants, water travels from the roots up through the stems and into the leaves, replacing the water used in photosynthesis and lost from the plant by evaporation.  Leaves  Structure:  Water evaporates from the inside of a leaf to the outside through stomata in a process called transpiration that helps pull the water column upward. Leaves  Function:  The main function of leaves is photosynthesis, and they have many adaptations to optimize this purpose.  Most leaves have a flattened portion called the blade with a large surface area.  Leaves  Function:  The blade is attached to the stem by a stalk called a petiole.  The petiole’s vascular tissue connects the stem’s vascular tissues to the leaf’s vascular tissue or veins. www.ens.sch.ae