Presentation on theme: "Angiosperms Introduction to the Structure of Flowering Plants."— Presentation transcript:
Angiosperms Introduction to the Structure of Flowering Plants
What is an Angiosperm? In Division Anthophyta; can be trees, shrubs, herbs, vines, etc., and found in all environments Have seeds, roots, stems, and leaves Produces flowers (specialized leaves) Produces seeds in a fruit, either fleshy or dry Divided into 2 classes, monocots (1 seed leaf) and dicots (2 seed leaves) Have sophisticated environmental adaptations
Roots Underground parts Anchor the plant Absorbs water/minerals Transports solutions up Stores nutrient starches; several edible Thin/thick; short/long; singular/branching
Cross section structure Epidermis with root hairs Outer cortex for transport/storage; some of it is parenchyma Waterproof endodermis around vascular cylinder Pericycle producing lateral roots Vascular cylinder of xylem, vascular cambium and phloem
Secondary root emerging from the pericycle
Xylem transports water and dissolved minerals up and outward to the rest of the plant Phloem transports the products of photosynthesis, like glucose, down and out to the rest of the plant Vascular tissues:
Stems Aboveground parts Support and display leaves and flowers Transport through many vascular tissues Stores some starches Produces leaf and flower buds by way of apical and lateral meristems
Herbaceous – soft and green as in small herbs and some shrubs Woody – firm as in shrubs and trees (old xylem provides our firewood from trees) Stem types
Cross-section structure (herbaceous) Vascular bundles of mixed xylem/phloem Surrounded by cortex of parenchyma tissue Vascular bundles scattered in monocots Bundles in an outer ring in dicots Epidermis outside; endodermis surrounding bundles Dicot?
Cross-section structure (woody) Cork (bark) outside Cork cambium produces cork Phloem layer Vascular cambium makes phloem outside/xylem inside Rings of annual growth of xylem
Leaves Waxy cuticle on top Upper epidermis layer Palisades parenchyma loaded with chlorophyll Spongy mesophyll with air gaps and veins of vascular tissue (gas exchange) Lower epidermis with numerous stoma Waxy cuticle underneath
Actual photomicrograph of leaf XS
Flowers Sepals from bud cover Colorful petals protect interior structures Stamens of filaments and pollen-laden anthers Pistil(s) with sticky stigma, long style, and egg-making ovary at the base All attached to a long peduncle May have all parts or a mixture of parts
The pollen, or male gametophyte (gamete-producing plant ) and the ovule, or female gametophyte, represent the sexual generation in the life-cycle of the flowering plant. The pollen may be transferred to the stigma of the same flower or to the stigma of another flower of the same species. In the former case the process is called self-pollination, in the latter case, cross-pollination. Pollination
Fertilization On the stigma, the pollen germinates, and produces the male gametes which are transported to the ovule in a pollen tube. One of these male gametes fuses with the female gamete within the ovule. This fusion, called fertilization, marks the beginning of the development of the embryo plant. The tissues of the ovule surrounding the embryo form the seed, while the tissues of the ovary, sometimes with some of the surrounding structures, form the fruit. The fruit is the ripened ovary (ovaries) with the enclosed seeds, if any, and in some cases may include other parts of the parent flower. The characteristics of the fruit are thus closely related to the characteristic of the flower (or flowers), and especially the ovary (or ovaries) from which it was produced.
Review (write down responses) The plants most familiar to you, including fruit trees, vegetables, cereal grains, and wildflowers are ____________________ Angiosperms and gymnosperms are alike in that they both have _________, _________, __________, and _____________. Angiosperms produce __________ and have their seeds in ___________. Flowering plants are in the division ____________ The 2 classes of anthophytes are ______________ and ___________________.
Grasses, orchids and lilies have 1 seed leaf and are called _________________; _____________ have 2 seed leaves. One advantage to plants having fruit-covered seeds is added protection for the _____________. Water and minerals enter the root by absorption into the ____________________. The size of the stomata is controlled by the ________ cells. Most photosynthesis occurs in the __________ ____________.
Transfer of pollen from the anther of one flower to the pistil of another is called ____________ pollination. The outermost structure on a flower is the ______________. Egg cells are produced in the __________ of the pistil. The seeds, and therefore the embryo, are protected by a structure called a _____________, either fleshy or dry.
The primary function of ____________ is to trap light energy for photosynthesis. Roots, stems, and leaves all function as ________ Cambium and apical meristem are examples of ___________ tissue. The plant anchor is the ____________. The plant’s version of water, sewer, and gas utilities would be the ____________ tissues. Plant food is transported in ____________ tissue. Water and dissolved minerals are transported in ___________ tissue.