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Plant Structure. Aquaponics. Plant Body. Shoot system = leaves + stem Root system Meristem = cells that divide for life of plant, can give rise to all plant structures 3 BASIC Organs Roots Stems Leaves. 2 BASIC Systems BOTH SYSTEMS DEPEND ON THE OTHER
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Plant Structure Aquaponics
Plant Body • Shoot system = leaves + stem • Root system • Meristem = cells that divide for life of plant, can give rise to all plant structures 3 BASIC Organs • Roots • Stems • Leaves
2 BASIC Systems • BOTH SYSTEMS DEPEND ON THE OTHER • Root System (roots) receive sugars and other nutrients from photosynthetic parts • Shoot System (leaves and stems) depends on water & minerals absorbed from the soil by roots.
The plant body cells tissues organs • A tissue = group of cells with a common structure and function • An organ = several types of tissues that work together to carry out particular functions
Tissue Types in Vascular Plants • Dermal Tissue • Covers/ protects plant • Makes cuticle on stems/ leaves • Allows for better H2O absorption (root hairs) • Make guard cells • Vascular Tissue (xylem & phloem) • Transport and support • Throughout the plant • Called “veins” in leaves • Called the “stele” in stem or root • Ground Tissue • Between dermal and vascular tissues • Storage • Photosynthesis (makes sugars) • Support Dermal tissue Ground tissue Vascular tissue
Plant Body- ROOTS Root Functions Anchors plant in soil Takes up water and minerals from soil
Eudicot and Monocot Roots Mono = 1 (1 BIG circle)
Eudicot and Monocot Roots • Epidermis-outer layer of root that protects the underlying tissues of the root. • Cortex-the inner side of the epidermis. Allows diffusion of water, mineral salts, and oxygen from the root hairs. Stores foods, especially starch. • Endoderims-Active mineral uptake
Modified Roots • Some plants have modified roots • Adventitious roots arise aboveground spread over large areas • Storage roots hold “food” called root tubers
Phloem transports sugar Xylem conducts water and minerals Plant Body-STEM Stem: series of nodes and internodes Functions Support for the plant body Holds leaves up to light Transports nutrients throughout plant
Tissue Organization of Stems • Most Eudicots • vascular tissue consists of vascular bundles that are arranged in a ring • Most Monocot stems • the vascular bundles are scattered throughout the ground tissue, rather than forming a ring Pith: in young stems, the pith stores food. The pith disappears in older stems. Cambium: during growing season, cambium produces new phloem to the outside and new xylem to the inside.
Division of Meristem Cells Causes Plant Growth • Apical Meristem • tips of root and shoot • increase in height • Lateral Meristem • cylinders within plant body • increase in width
Types of Meristems (like embryonic stem cells) • Apical meristems are located at the tips of roots and in the buds of shoots • elongate shoots and roots, a process called primary growth • Lateral meristems • add thickness ONLY to woody plants, a process called secondary growth • 2 lateral meristems: the vascular cambium and the cork cambium • vascular cambium adds layers of vascular tissue called secondary xylem (wood) and secondary phloem • cork cambium replaces the epidermis with periderm, which is thicker and tougher (bark)
Woody Stem Growth • The stem has three areas: • Bark • Wood • pith SUMMER WOOD (late wood): the part of an annual ring of wood, characterized by compact, thick-walled cells, formed during the later part of the growing season. CORK-protects the outer part of the bar SPRING WOOD (early wood): the part of an annual ring of wood, characterized by large, thin-walled cells, formed during the first part of the growing season.
HOW OLD IS THIS TREE? Secondary phloem Vascular cambium Cork cambium Late wood Secondary xylem Periderm LE 35-18b Early wood Cork Transverse section of a three-year- old Tilia (linden) stem (LM) Xylem ray Bark 0.5 mm 0.5 mm
Blade Petiole Plant Body-LEAF REVIEW Leaf = blade + petiole Functions Exposes surface to sunlightMajor site of photosynthesisConserves waterProvides for gas exchange Stoma = opening in the leaf for gas exchange, water evaporation
Monocots & Eudicots Leaves • Monocots lack petioles • Base of leaf forms a sheath that envelops stem • Have parallel veins (run length of the blade) • Eudicot (dicot) have petioles & leaves have a multibranched network of major veins. • Petiole • Only Eudicots NOT Monocots petiole
Flower Mitosis Meiosis Mitosis Pollengrains Ovule Flowering Plant Reproduction • Flowers are modified leaves, specialized for reproduction (where pollination takes place). • Flower parts undergo meiosis to produce haploid products • pollen grain • ovule (contains egg cell)
Development of Fruit and SeedsFrom Flower Parts Providesnutrition Endosperm Triploid Endosperm Cell FreshFruit Ovary SeedCoat Integument DiploidZygote Embryo(new plant) • Seed = embryo + stored food + seed coat • Fruit = ovary wall, mechanism for seed dispersal
Flowers, Fruits, and vegetables A fruit is the part of the plant that develops from a flower. It's also the section of the plant that contains the seeds. (Protects the seeds). The other parts of plants are considered vegetables. These include the stems, leaves and roots — and even the flower bud.
Dead Center sits the tomato. Why? Botanically speaking, a tomato is a fruit because it is a seed-bearing structure that develops from the ovary of a flowering plant. In the culinary world sweet = fruits and savory = vegetables: this includes botanical fruits as eggplants, bell peppers, and tomatoes.
Angiosperm Classification and Morphology • Monocots: grasses, lilies, orchids, corn, palms, onions • Dicots (aka-Eudicots): broadleaf trees, shrubs, most flowers, and vegetables.
Exit Slip-March 12, 2014 • Draw a picture of a monocot and dicot cross section of a ROOT. • Draw a picture of a monocot and dicot cross section of a STEM.