Biology Sylvia S. Mader Michael Windelspecht Chapter 27 Flowering Plants: Reproduction Lecture Outline See separate FlexArt PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes. 1 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1

Sexual Reproduction in Flowering Plants Biology, 9th ed, Sylvia Mader Chapter 28 Slide #2 Sexual Reproduction in Flowering Plants Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 8 mitosis anther 1 7 sporophyte seed 2 ovule zygote diploid(2n) ovary 6 FERTILIZATION MEIOSIS haploid(n) 3 microspore egg megaspore sperm 4 5 mitosis Male gametophyte (pollen graIn) Female gametophyte (embryo sac) 2

Sexual Reproductive Strategies Biology, 9th ed, Sylvia Mader Chapter 28 Sexual Reproductive Strategies Reproduction in Plants A flower produces Microspore - Male gametophyte Becomes pollen grain Megaspore - Female gametophyte Becomes the female gametophyte, an embryo sac within an ovule within an ovary Ovule becomes a seed Ovary becomes a fruit

Biology, 9th ed, Sylvia Mader Chapter 28 Anatomy of a Flower Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. stamen carpel anther stigma filament style ovary petal ovule receptacle sepal peduncle

Sexual Reproductive Strategies Biology, 9th ed, Sylvia Mader Chapter 28 Sexual Reproductive Strategies Reproduction in Plants Sepals protect the bud Petals attract pollinators Stamens: male Anther - Saclike container Filament - Slender stalk Carpel: female Stigma - Enlarged sticky knob Style - Slender stalk Ovary - Enlarged base enclosing ovules

Sexual Reproductive Strategies Biology, 9th ed, Sylvia Mader Chapter 28 Sexual Reproductive Strategies Reproduction in Plants Complete vs. incomplete flowers: Complete flowers have sepals, petals, stamens, and a carpel Incomplete flowers are missing one or more of above Perfect vs. imperfect flowers: Perfect (bisexual) Imperfect (unisexual)

Life Cycle of Flowering Plants Biology, 9th ed, Sylvia Mader Chapter 28 Slide #7 Life Cycle of Flowering Plants Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. anther Development of the male gametophyte: Development of the female gametophyte: In pollen sacs of the anther , a microspore mother cell undergoes meiosis to produce 4 microspores each In an ovule within an ovary, a megaspore mother cell undergoes meiosis to Produce 4 megaspores. Mature Seed seed coat anther The ovule develops into a seed containing the embryonic sporophyte and endosperm. mitosis ovule Pollen sac ovary Ovule ovary embryo endosperm (3n) microspore mother cell megaspore mother cell Sporophyte Seed diploid (2n) DOUBLE FERTILIZATION MEIOSIS MEIOSIS haploid (n) ovule wall Pollination tube cell Microspores During double fertilization, one sperm from the Male gametophyte Will fertilize the egg; another Sperm will join with polar nuclei to produce the 3n endosperm. Development of the sporophyte: generative cell Megaspores Pollination occurs; a pollen grain germinates and produces a pollen Microspores develop into male gametophytes (pollen grains). mitosis megaspore pollen tube ovule Pollen grain (male gametophyte) wall 3 megaspores disintegrate sperm antipodals One megaspore becomes the embryo sac (female gametophyte). mitosis integument Mature male gametophyte polar nuclei micropyle polar nuclei tube cell nucleus egg cell synergids egg sperm Embryo sac (mature female gametophyte) (Top): Courtesy Graham Kent; (Bottom): © Ed Reschke 7

Sexual Reproductive Strategies Biology, 9th ed, Sylvia Mader Chapter 28 Sexual Reproductive Strategies Reproduction in Plants Pollination Transfer of pollen Self-pollination vs. Cross-pollination Fertilization Pollen lands on stigma, germinates, forming a pollen tube Mature seed contains the embryo, stored food, & seed coat

Development of an Eudicot Embryo Biology, 9th ed, Sylvia Mader Chapter 28 Development of an Eudicot Embryo Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Arabidopsis thaliana endosperm endosperm nucleus embryo suspensor zygote basal cell 1 2 Proembryo stage: Embryo (green) is multicellular and the suspensor (purple) is functional. zygote Zygote stage: Double fertilization results in zygote (true green) and endosperm. (Proembryo): Courtesy Dr. Chun-Ming Liu; (Torpedo): © Biology Media/Photo Researchers, Inc.; (Mature embryo): © Jack Bostrack/Visuals Unlimited

Development of an Eudicot Embryo (continued) Biology, 9th ed, Sylvia Mader Chapter 28 Slide #10 Development of an Eudicot Embryo (continued) Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. A. thaliana A. thaliana Capsella Capsella hypocotyl (root axis) epicotyl (shoot apical meristem) shoot apical meristem bending cotyledons endosperm cotyledons appearing seed coat endosperm root apical meristem radicle (root apical meristem) cotyledons 3 4 Heart stage: Embryo is heart shaped. 5 Torpedo stage: Embryo is torpedo shaped; the cotyledons are obvious. 6 Mature embryo stage: The epicotyl will be the shoot system; the hypocotyl will be the root system. Globular stage: Embryo is globe shaped. (Proembryo): Courtesy Dr. Chun-Ming Liu; (Torpedo): © Biology Media/Photo Researchers, Inc.; (Mature embryo): © Jack Bostrack/Visuals Unlimited 10

Biology, 9th ed, Sylvia Mader Chapter 28 Monocot vs. Eudicot Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. seed coat plumule pericarp hypocotyl endosperm coleoptile radicle cotyledon embryo embryo cotyledon plumule radicle coleorhiza a. b. a: © Dwight Kuhn; b: Courtesy Ray F. Evert/University of Wisconsin Madison

Biology, 9th ed, Sylvia Mader Fruits Chapter 28 Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Drupe True Berry chamber of ovary has many seeds exocarp pericarp exocarp (skin) mesocarp (flesh) endocarp (pit contains seed) a. A drupe is a fleshy fruit with a pit containing a single seed produced from a simple ovary. b. A berry is a fleshy fruit having seeds and pulp produced from a compound ovary. Legume Samara seed covered by pericarp wing pericarp seed c. A legume is a dry dehiscent fruit produced from a simple ovary. d. A samara is a dry indehiscent fruit produced from a simple ovary . Aggregate Fruit Multiple Fruit fruit from many ovaries of a single flower e. An aggregate fruit contains many fleshy fruits produced from simple ovaries of the same flower. one fruit fruits from ovaries of many flowers f. A multiple fruit contains many fused fruits produced from simple ovaries of individual flowers. a, b: © Kingsley Stern; c: © Dr. James Richardson/Visuals Unlimited; d: © James Mauseth; e: Courtesy Robert A. Schlising; f: © Ingram Publishing/Alamy

Fruit Dispersal by Animals Biology, 9th ed, Sylvia Mader Chapter 28 Fruit Dispersal by Animals Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a. b. a: © Marie Read/Animals Animals/Earth Scenes; b: © Scott Camazine/Photo Researchers, Inc.

Fruit Types and Seed Dispersal Biology, 9th ed, Sylvia Mader Chapter 28 Fruit Types and Seed Dispersal Reproduction in Plants Seed Germination Embryo resumes growth & metabolic activity Length of viability is variable Some seeds do not germinate until they have been through a dormant period Temperate zones - Cold Weather

Fruit Types and Seed Dispersal Biology, 9th ed, Sylvia Mader Chapter 28 Fruit Types and Seed Dispersal Reproduction in Plants Environmental requirements for seed germination Availability of oxygen for metabolic needs Adequate temperature for enzyme activity Adequate moisture for hydration of cells

Eudicot and Monocot Seed Structure and Germination Biology, 9th ed, Sylvia Mader Chapter 28 Eudicot and Monocot Seed Structure and Germination Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. cotyledons (two) pericarp plumule endosperm hypocotyl cotyledon (one) radicle coleoptile plumule seed coat radicle cotyledon coleorhiza Seed structure Corn kernel true leaf first true leaves (primary leaves) epicotyl withered cotyledons first leaf seed coat cotyledons (two) hypocotyl coleoptile prop root coleoptile radicle hypocotyl secondary root adventitious root primary root primary root primary root coleorhiza Bean germination and growth Corn germination and growth a. a: © Ed Reschke; b: © James Mauseth b.

Asexual Reproduction in Plants Biology, 9th ed, Sylvia Mader Chapter 28 Asexual Reproduction in Plants Reproduction in Plants Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parent plant stolon Asexually produced offspring © G.I. Bernard/Animals Animals/Earth Scenes