Plant Anatomy: Internal Structure and Tissue Systems
Plant Anatomy: Internal Structure and Function
Plant anatomy, also known as phytotomy, is the study of the internal structure of plants. While plant morphology deals with external forms, anatomy dives into the microscopic organization of cells and tissues to understand how a plant functions and survives.
1. Introduction, Objective, and Scope
- Objective: To understand the structural organization of the plant body and how internal structures are specialized for functions like photosynthesis, transport,
Plant Anatomy: Secondary Growth, Xylem Transport, and Drought Adaptations
Xylem Pit Functionality in Angiosperms and Gymnosperms
Pits regulate the flow of water and solutes within the xylem. They are formed by the deposition of the endoplasmic reticulum on the primary wall, which prevents the formation of the secondary wall in these areas. When the organelle disappears, a thin cavity of primary wall remains. Subsequently, the primary wall is hydrolyzed, leaving a thin network of cellulose through which water and solutes can pass.
Comparison of Pit Structures
- Gymnosperms:
Plant Biology Essentials: Reproduction, Anatomy, and Metabolism
Reproductive Strategies: Bryophytes to Angiosperms
Understanding the reproductive differences between plant groups reveals significant adaptive and evolutionary implications. Bryophytes and pteridophytes are seedless plants, reproducing primarily by spores. In contrast, gymnosperms and angiosperms are spermatophytes, characterized by the presence of seeds.
A key distinction lies in their life cycles: spermatophytes exhibit a very reduced haploid phase, whereas bryophytes and pteridophytes have a dominant
Read MorePlant Tissues and Organs: Structure and Function
1. Meristematic Tissue
MeriStar: Primary Meristem
Responsible for plant growth. Growth in length occurs in the terminal buds of the stem and root.
MeriStar Side: Secondary Meristem
Growth in thickness, arising from the first year of life. Two types:
- Cambium: Internal, causes the conducting vessels.
- Phellogen: External, originates suber or cork.
2. Adult Tissue
ECJ. Parenchymatous Tissue
Forms the major part of the plant; it is a tissue filler. Four types:
- Parenchyma Chlorophyll: Cells have chlorophyll, enabling
Leaf Morphology: Structure, Development, and Types
Leaf Structure: Stem body, limited growth, dorsiventral symmetry, specialization to perform photosynthesis.
Leaf Parts
Pod: Widening rather than union with the stem. Petiole: Called up, leaf blade joins the stem when present. Lamina (Limbo Foliar): Simple leaf (pulvinus motor, rachis, rachilla, leaflets or pinnae, foliólulos or pinnules).
Foliar Succession (Phyllome)
Used to refer to all types of leaves of a plant:
- Cataphylls (Scales): Appear in the winter buds of underground stems, called Perula together.
Root Structure and Development in Plants
Root Cap Function and Origin
The root cap, or cofa, is a structure that protects the apical meristem of the root as it grows and penetrates the soil. It is composed of living parenchymal cells derived from the apical meristem. It originates from the caliptrogen in monocots and the calyptra-dermatogen in dicots. The root tip secretes mucilage, which aids in ion exchange, adherence to soil particles, and nutrient chelation. Root georeaction (response to gravity) is controlled by Ca++ and the hormone
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