Angiosperms: Characteristics, Classification, and Importance, Slides of Botany and Agronomy

Download Angiosperms: Characteristics, Classification, and Importance and more Slides Botany and Agronomy in PDF only on Docsity! Angiosperms Docsity.com Angiosperms are flowering plants. • They have true roots, stems, leaves and flowers... • Angiosperms are more highly evolved that the algae, mosses, fungi and ferns. Docsity.com Chars of Angiosperm Cotyledons – The cotyledons are the "seed leaves" produced by the embryo. They serve to absorb nutrients packaged in the seed, until the seedling is able to produce its first true leaves and begin photosynthesis. Docsity.com Pollen structure -- • The first angiosperms had pollen with a single furrow or pore through the outer layer (monosulcate). This feature is retained in the monocots, • but • most dicots are descended from a plant which developed three furrows or pores in its pollen (triporate). Docsity.com Number of flower parts -- • If you count the number of petals, stamens, or other floral parts, you will find that monocot flowers tend to have a number of parts that is divisible by three, usually three or six. • Dicot flowers on the other hand, tend to have parts in multiples of four or five (four, five, ten, etc.). • This character is not always reliable, however, and is not easy to use in some flowers with reduced or numerous parts. Docsity.com Stem vascular arrangement -- • Vascular tissue occurs in long strands called vascular bundles. • These bundles are arranged within the stem of dicots to form a cylinder, appearing as a ring of spots when you cut across the stem. • In monocots, these bundles appear scattered through the stem, with more of the bundles located toward the stem periphery than in the center. This arrangement is unique to monocots and some of their closest relatives among the dicots. Docsity.com Root development -- • In most dicots the root develops from the lower end of the embryo, from a region known as the radicle. • The radicle gives rise to an apical meristem which continues to produce root tissue for much of the plant's life. • By contrast, the radicle aborts in monocots, and new roots arise adventitiously from nodes in the stem. These roots may be called prop roots when they are clustered near the bottom of the stem. Docsity.com Secondary growth -- • Most seed plants increase their diameter through secondary growth, producing wood and bark. • Monocots (and some dicots) have lost this ability, and so do not produce wood. • Some monocots can produce a substitute however, as in the palms and agaves. Docsity.com They also have seeds. • The seeds are formed when an egg or ovule is fertilized by pollen in the ovary. • The ovary is within a flower. • The flower contains the male and/or female parts of the plant. • Fruits are frequently produced from these ripened ovaries. Docsity.com d fruit of the banana Figure 19-3b . Biology of Plants, Seventh Edition Docsity.com spa a gag ee eee ne ee ees  Figure 19-3c Biology of Plants, Seventh Edition 9 2005 W.H, Freeman and Company ® Docsity.com  Receptacle gure 19-6b jplogy of Plants, Seventh Edition 9 2005 W.H. Freeman and Company Docsity.com Stigma Anther Carpel Stamen . Filament #) Petal (petals = corolla) Receptacle Sepal (sepals = calyx) Peduncle (>) Perianth= calyx + corolla Docsity.com Position of ovary w/ respect to sepals and petals and stamens Docsity.com Anther Filament ™~ Receptacle Figure 19-14 Biology of Plants, Seventh Edition (© 2005 W.H. Freeman and Company Docsity.com Tube cell Generative cell ‘igure 19-16 ialog\hof Plants, Seventh Edition . H. Freeman and Company  Docsity.com P) of Plants, Seventh Edition W. H. Freeman and Company  Sperm cells Tube nucleus Figure 19-20 Biology of Plants, Seventh Edition © 2005 W.H. Freeman and Company Docsity.com  Flowers a Leaflet: Trifoliolate x leaf Petiole ‘ | Axillary buds Taproot system Figure 19-22 part 5 Biology of Plants, Seventh Edition © 2005 W.H. Freeman and Company Docsity.com Anther_ —— (“Pollen sac with Tetrads &) res microsporocytes of microspot ® (2n) (n) 7 “aaa \ Leaflets Trifoliolate leaf Petiole Axillary buds Unifoliolate leaf Cotyledons Hypocotyl a ~~! Roots (pod) Ge Primary root Germinating Seed Taproot Young gaa system seedling Figure 19-22 Biology of Plants, Seventh Edition 2005 W.H. Freeman and Company Pollen grain Germinating ——_— Pe —__ {\ pollen grains Generative cell on stigma —_—.. scons Y Sperm —-_. _ Mat I Ovule with Integum: emetopiye Trobe nucleus megasporocyte Megaspores 2-Nucleate (2n) (n embryosac a. Nucleate 1 oun tie embryo sac é 2 Polar nuclei \ a (n+n) 7-Celled, 8-1 nba \ embryo sac (mature Fenieaton| tube megagametophyte ‘S) primary Zz endosperm ‘ygote (2n) nucleus | E ah 2-Celled proembryo Embryo & Endosperm (3n) Embryo (heart stage) ¥° endosperm ‘Seed coat Seed Docsity.com Pollen tube Primary & Zygote endosperm (2n) nucleus (3n) 2-Celled proembryo ? sac Endosperm (3n) Embryo (heart stage) Hypocotyl- Fruit root axis )Embryo ) (pod) Cotyledo Endosperm © Seed coat eed Seed 19-22 part 3 lof Plants, Seventh Edition W.H. Freeman and Company Docsity.com  % Trifoliolate - leaf Petiole | Axillary buds Unifoliolate leaf Fruit 2s Cotyledons (pod) + — Hypocotyl \ Roots ) mh — a Primary root Oo rap Ai inati Seed \ Taproot Young Germinating system seedling seed Figure 19-22 part 4 Biology of Plants, Seventh Edition Cy H.Freeman and Company S Docsity.com