Plant Reproduction and Development PDF

Plant Reproduction and Development Plants are among the most successful organisms on the planet. Their success can be attributed to various biological adaptations that let them thrive many habitats. 2  The ability of plants to alter between reproduction...

Plant Reproduction and Development Plants are among the most successful organisms on the planet. Their success can be attributed to various biological adaptations that let them thrive many habitats. 2  The ability of plants to alter between reproduction and development allowed to colonize environments with diverse conditions. 3 Plants have also evolved various reproductive structures to Magnolia flower Fern spores allow them to increase their chances of successful fertilization and development. Gymnosperm cones Passionfruit flower 4 Review of Plant Characteristics Life cycle with Multicellular Cellulosic alternation of organisms cell wall generations Photosynthetic Plastids in capacity cytoplasm 5  Review of Major Plant Groups } Hornworts Non-Vascular spore-bearing Liverworts non-vascular Plants plants lignified vascular Mosses Land tissues absent Plants spore-bearing vascular plants Pteridophytes Vascular Plants Gymnosperms Spermatophyte cone-bearing plants lignified vascular tissues present s seed-bearing Angiosperms vascular plants flowering plants6  Review of Major Plant Groups Bryophytes (Spore-bearing non-vascular plants) Hornworts Liverworts Mosses 7  Review of Major Plant Groups Pteridophytes (Spore-bearing vascular plants) Ferns Horsetails Lycophytes 8  Review of Major Plant Groups Spermatophytes (Seed-bearing vascular plants) Gymnosperms Angiosperms Angiosperms (Monocot) (Dicot) 9 Alternation of Generations Common life cycle pattern for green plants Alternation of haploid and diploid phases Sporophyte is the diploid stage, while gametophyte is haploid Meiosis forms haploid spores, mitosis forms haploid gametes Diploid chromosome number is restored through fertilization 10 Floral Anatomy The pistil consists of the female structures in flowers (i.e., stigma, style, ovary) 11 Floral Anatomy The stigma is a structure where the pollen grains must land during pollination. 12 Floral Anatomy Style is the stalk of the stigma that leads to the ovary. Within it is the pollen tube. 13 Floral Anatomy Ovary is the female structure in flowers that house the female gametes. 14 Floral Anatomy Ovules are small structures within the ovary. Each of them contains an egg nucleus. 15 Floral Anatomy Stamen refers to the male portion of the flower. It consists of anthers and filaments. 16 Floral Anatomy Anther is the male structure that produces and stores the pollen grains. 17 Floral Anatomy Filament is the staminal structure that serves as the stalk of the anther. 18 Floral Anatomy Petals are the colorful leaf-life structures in flowers that primarily attract pollinators. 19 Floral Anatomy Sepals are green leaf- like structures that protect the structures in a flower bud. 20 Floral Anatomy Receptacle is the thickened portion below the ovary where floral structures grow. 21 Floral Anatomy Pedicel is the stalk of the flower which provides support to all floral parts. 22  Angiosperm Life Cycle The seeds inside a fruit contain the developing embryos. It is the first sporophyte stage. 23  Angiosperm Life Cycle The embryos undergo development and differentiation to become seedlings. The seeds inside a fruit contain the developing embryos. It is the first sporophyte stage. 24  Angiosperm Life Cycle Continuous growth and development allows a seedling to reach maturity. The embryos undergo development and differentiation to become seedlings. The seeds inside a fruit contain the developing embryos. It is the first sporophyte stage. 25  Angiosperm Life Cycle Continuous growth and The adult stage becomes development allows a sexually mature. seedling to reach maturity. The embryos undergo development and differentiation to become seedlings. The seeds inside a fruit contain the developing embryos. It is the first sporophyte stage. 26  Angiosperm Life Cycle Continuous growth and The adult stage becomes development allows a sexually mature. seedling to reach maturity. The embryos undergo development and differentiation to The adults now produce become seedlings. gametophytes in pollens and ovules. The seeds inside a fruit contain the developing embryos. It is the first sporophyte stage. 27  Angiosperm Life Cycle Continuous growth and The adult stage becomes development allows a sexually mature. seedling to reach maturity. The embryos undergo development and differentiation to The adults now produce become seedlings. gametophytes in pollens and ovules. The seeds inside a fruit contain the developing Fusion of the gametes embryos. It is the first occurs during sporophyte stage. pollination. 28  Angiosperm Life Cycle Continuous growth and The adult stage becomes development allows a sexually mature. seedling to reach maturity. The embryos undergo development and differentiation to The adults now produce become seedlings. gametophytes in pollens and ovules. Thereafter, the ovary develops into a fruit. The ovules become seeds. The seeds inside a fruit contain the developing Fusion of the gametes embryos. It is the first occurs during sporophyte stage. pollination. 29  Gymnosperm Life Cycle Female Cones Male Cones 30  Gymnosperm Life Cycle Embryos develop into seedlings and into mature sporophyte. 31  Gymnosperm Life Cycle Upon reaching sexual maturity, gametophytes are produced in the male and female cones. Embryos develop into seedlings and into mature sporophyte. 32  Gymnosperm Life Cycle Upon reaching sexual maturity, gametophytes are produced in the The pollens from the male male and female cones. cones pollinate the ovules in female cones. Embryos develop into seedlings and into mature sporophyte. 33  Gymnosperm Life Cycle Upon reaching sexual maturity, gametophytes are produced in the The pollens from the male male and female cones. cones pollinate the ovules in female cones. Fertilization occurs, which Embryos develop into transforms seedlings and into ovules into seeds. mature sporophyte. 34  Fern Life Cycle Spores at the underside of fertile fronds A heart-shaped, free-living (sporophyte) of a fern species gametophyte of a fern species 35  Fern Life Cycle The young sporophyte develops into mature ferns. 36  Fern Life Cycle Fertile ferns produce spores through meiotic division. The young sporophyte develops into mature ferns. 37  Fern Life Cycle Fertile ferns The spores from produce spores the sporangium through develop into meiotic gametophytes. division. The young sporophyte develops into mature ferns. 38  Fern Life Cycle Fertile ferns The spores from produce spores the sporangium through develop into meiotic gametophytes. division. The mature gametophyte produces eggs and sperms. The young sporophyte develops into mature ferns. 39  Fern Life Cycle Fertile ferns The spores from produce spores the sporangium through develop into meiotic gametophytes. division. The mature gametophyte produces eggs and sperms. The young Fertilization sporophyte occurs, which develops into forms the mature ferns. zygote. 40  Fern Life Cycle Fertile ferns The spores from produce spores the sporangium through develop into meiotic gametophytes. division. The mature gametophyte produces eggs and sperms. The diploid zygote develops into a young sporophyte. The young Fertilization sporophyte occurs, which develops into forms the mature ferns. zygote. 41  Comparison of Reproductive Structures and Processes Structures and Pteridophytes and Angiosperm Gymnosperm Processes Bryophytes Floral Structures Present Absent Absent Cones Absent Present Absent Primary Dispersal Seeds Seeds Spores Structures Pollination Present Present Absent Fruit Formation Present Present Absent Some sporophyte, Dominant Stage Sporophyte Sporophyte some gametophyte 42 Forms of Reproduction in Angiosperms Asexual Reproduction Sexual Reproduction 43  Forms of Reproduction in Angiosperms Asexual Reproduction Sexual Reproduction May either involve single (self- Requires a single or lone parent pollination) or two parents (cross-pollination) 44  Forms of Reproduction in Angiosperms Asexual Reproduction Sexual Reproduction May either involve single (self- Requires a single or lone parent pollination) or two parents (cross-pollination) Does not involve the fusion of Requires the fusion of a sperm gametes cell and egg cell during fertilization 45  Forms of Reproduction in Angiosperms Asexual Reproduction Sexual Reproduction May either involve single (self- Requires a single or lone parent pollination) or two parents (cross-pollination) Does not involve the fusion of Requires the fusion of a sperm gametes cell and egg cell during fertilization Offspring are genetically Enhances genetic variation identical to the parent organism because the parents and offspring are not genetically identical 46  Asexual Reproduction: Apomixis Floral units/flowers Mature fruits and seeds Apomixis in some species of dandelions allows the production of embryos from unfertilized eggs in ovules. 47  Asexual Reproduction: Apomixis Apomixis is a genetic feature in dandelions, which therefore, allows them to produce viable seeds without undergoing pollination. 48 Asexual Reproduction: Vegetative Propagation Vegetative propagation allows plant parts to produce buds that can develop into new individuals. 49  Asexual Reproduction: Vegetative Propagation Stolon Stolon Stolon Main Plant Buds Bud Strawberries (Fragaria sp.) performs vegetative propagation through the buds that emerge from stolons or runners. 50 Sexual Reproduction: Pollen Grains Pollen grains contain the male gametophytes in angiosperms. Each pollen grain consists of two sperm nuclei from the generative nucleus. The tube nucleus will transport the sperm during pollination. 51 Sexual Reproduction: Ovules Each ovule or embryo sac in the ovary of the flower consist of eight nuclei. The primary sex cell that is fertilized is the egg nucleus or egg cell. Only the polar nuclei and egg nucleus will have descendant in seeds. 52  Fertilization happens one the pollen penetrates the ovary of the flower. A fertilized ovule then develops to form a fruit containing the seeds that must be dispersed to produce new individuals, which will sexually mature. 53 Sexual Reproduction: Double Fertilization Pollen grains land on the stigma of the pistil. The pollen tube extends itself. The pollen tube moves down the style towards alongside two sperm nuclei. In the embryo sac, one of the sperm nuclei fertilizes the egg nucleus to form embryo. The other sperm nucleus fertilizes the polar nuclei to produce endosperm. Double fertilization produces a diploid embryo and a triploid endosperm. 54 Sexual Reproduction: Double Fertilization The fate of the sperm nuclei, egg nucleus, and polar nuclei during double fertilization in angiosperms 55 Plant Development: Embryogenesis The fate of different floral structure upon the maturity into a fruit 56 Plant Development: Embryogenesis The differentiation of the ovary wall into exocarp, mesocarp, and endocarp in different types of fruits 57  In a generalized angiosperm life cycle, a plant starts as a seed. ○ The seed imbibes water for activation, and it develops and forms a seedling. ○ The seedling will reach an adult tree that will bloom and produce flowers. ○ The flowers contain the pollen from the anther and ovule in the pistil that is needed for fertilization. 58  Plant Development: Organogenesis During germination, water is imbibed, which ruptures the seed coat. The radicle emerges from the seed, which becomes the root of the plant. The hypocotyl emerges from the seed, which become the stem. The cotyledons serve as the primary embryonic leaves in the seedlings. The fate of plumule, hypocotyl, cotyledons, Eventually, the epicotyl from plumule gives rise to mature leaves. radicle, and epicotyl in the developing seedlings 59  Both embryogenesis and organogenesis are important processes that take place after the formation of seeds in a plant. They ultimately lead to the formation of functional organs in a plant body. 60 The general pattern of reproductive and developmental phases of the plant life cycle 61