Seed plants are known as Gymnosperms Flowering plants are known as Angiosperms In gymnosperms, the megaspore develops into... The female gametophyte within the old megasporangium In seed plants, these are formed with egg cells and fertilized in situ Archegonia Tissue composing the chief part of the young ovule, in which the embryo sac develops Nucellus The embryo develops surrounded by gametophyte tissue and old megasporangium wall, which is known as Nucellus The megasporophyll surrounds the nucellus and acts as Integument (seed coat) Seed coat Integument When mature, this is released from the plant (old sporophyte) Ovule (seed) Microsporophylls produce these Microsporangia Microspores are not released from the microsporangium, but divide to form a 4-celled... Microgametophyte Pollen grain A male microgametophyte In gymnosperms, pollen grains are release from this Strobilus The four cells that make up a pollen grain are 2 prothallial cells, 1 generative cell, and 1 tube cell The pollen grains germinate forming this A pollen tube This divides to form sperm nuclei which travel down the pollen tube to fertilize the egg The generative cell Reasons why seeds evolved (1) Embryo is well protected in the seed coat; (2) Seeds can be dormant and wait for suitable growth conditions; (3) Transfer of pollen does not require water like sperm; (4) Embryo has a supply of nutrients for early development; (5) A seed is an excellent dispersal unit. These gymnosperms are monoecious, woody perennials producing cones Coniferophyta Conifers have this type of life cycle An extended (3 year) life cycle Primary tissues are derived from these Meristems Secondary tissues are derived from these Cambia Cambial activity generally does this Increases the girth of the plant Woody plants develop these two types of cambia Vascular, Cork Vascular cambia produces Secondary xylem and phloem Cork cambia produces Bark layers Examples of deciduous conifers Larch, Bald Cypress "Growth rings" are actually these Secondary xylem The ground tissue occupying the center of the stem or root within the vascular cylinder Pith These are composed of thin-walled parenchyma (living) cells which disintegrate after the wood dries Wood rays Male cones Staminate cones Female cones Ovulate cones For Pines, these are usually lower on the tree Male cones Examples of southern hemisphere conifers Podocarps, araucarias This division includes the firs Coniferophyta Monoecious gymnosperms Coniferophyta, Gnetophyta This division of gymnosperms consists of woody perennials Coniferophyta This division of gymnosperms is known for having large female cones Cycadophyta Dioecious gymnosperms Cycadophyta, Ginkgophyta This division of gymnosperms consists of perennials with coarse palm-like leaves Cycadophyta This division of gymnosperms produces flagellated sperm Cycadophyta This division of gymnosperms is primarily tropical Cycadophyta These divisions of gymnosperms have male and female trees Cycadophyta, Ginkgophyta This division of gymnosperms is probably extinct in the wild Ginkgophyta The one and only species of Ginkgophyta Ginkgo biloba Dioecious trees Have separate male and female trees Female ovules of Ginkgophyta produce this smelly byproduct Butyric acid This is known for tolerating air pollution well Ginkgophyta This division of gymnosperms is known for having double fertilization Gnetophyta This division of gymnosperms is known for having vessels in the xylem Gnetophyta This division of gymnosperms does not produce multicellular archegonia Gnetophyta This gymnosperm has tropical vines with flowering plant-like leaves Gnetum This gymnosperm is a desert shrub Ephedra This gymnosperm is a tap-rooted perennial of SW Africa Welwitschia mirabilis These are the primary source of lumber Gymnosperms These are the primary source of pulp for paper Gymnosperms This gymnosperm provided an anti-cancer drug Taxus This gymnosperm provides flavor for gin The "berries" from Juniperus These are sources of amber Gymnosperms These are sources of lemon flavoring Gymnosperms These are sources of turpentine resins Gymnosperms These are known as "ferns with cones" Cycadophyta The largest group in the plant kingdom Anthophyta These produce seed plants without archegonia Anthophyta This division has a highly reduced gametophyte generation Anthophyta Two classes of Anthophyta Liliopsida, Magnoliopsida These are known as flowering plants Anthophyta Monocot or Dicot: Only one cotyledon in the embryo Monocots Monocot or Dicot: Leaves with parallel veins Monocots Monocot or Dicot: Flower parts in 3's Monocots Monocot or Dicot: Stem with an atactostele Monocots Monocot or Dicot: No true secondary growth Monocots Monocot or Dicot: Two cotyledons in the embryo Dicots Monocot or Dicot: Leaves with net veins Dicots Monocot or Dicot: Flower parts in 4's and 5's Dicots Monocot or Dicot: Stem with an eustele Dicots Monocot or Dicot: Many with secondary growth Dicots A typical flower has: Petals, sepals, carpels, stamens Primitive flowers... Are those with many separate parts with both stamens and carpels Advanced flowers... Are those that have undergone fusion of parts and reduction in numbers of each part; Some have separate male and female flowers Corolla All the petals of a flower Calyx All the sepals of a flower Perianth All petals and sepals Stamen Composed of an anther and filament; produces the pollen. Anther The pollen-bearing portion of the stamen Filament Supports the stamen Style A slender column of tissue that arises from the top of the ovary and through which the pollen tube grows. Androceium All stamens Carpel Contains the ovules, which develop into seeds after fertilization Pistil Fused carpels Gynoecium All female parts Receptacle The part of the flower stalk to which the flower parts are attached Hypogynous flower All parts attached below the ovary Epigynous flower All parts attached above the ovary Perigynous flower Flower parts attached to a floral cup or hypanthium Perfect flowers Have both stamens and carpels Imperfect flowers Produce only stamens, or only carpels Complete flowers Have all 4 parts (stamens, carpels, petals, sepals) Incomplete flowers Missing one or more parts (stamens, carpels, petals, sepals) Inflorescence The flowering branch Stigma The region of a carpel that serves as a receptive surface for pollen grains and on which they germinate For angiosperms, surrounded by the integuments, the megaspore mother cell does this Undergoes meiosis, producing 4 megaspores In angiosperms, the mature embryo sac is also known as The female gametophyte In angiosperms, the embryo sac contains 7 cells with 8 nuclei Exine The resistant outer wall of the pollen grain Intine Inner wall of pollen grain The exine is composed of this Sporopollenin These cells are present in the pollen grain Tube cell and generative cell Pollination When pollen grains are released from an anther and carried to a carpel/pistil Sperm nucleus fuses with the egg nucleus to become this Embryo The non-fertilizing sperm nucleus does this Fuses with the polar nuclei forming the primary endosperm nucleus which develops into the endosperm Double fertilization The involvement of a sperm cell fusing with the egg and another sperm cell fusing with the polar nuclei Endosperm Tissue that serves as food for the growing embryo Fruit Derived from the ripened ovary and sometimes other floral parts Pericarp The fruit wall Zygomorphic Bilateral symmetry Actinomorphic Radial symmetry The fruit wall is composed of three layers Exocarp, mesocarp, endocarp Multiple fruits Derived from many flowers Aggregate fruits Derived from several separate carpels of one flower Simple fruits Derived from one carpel of one flower Fruit type: Pineapple Multiple fruit Fruit type: Mulberry Multiple fruit Fruit type: Strawberry Aggregate fruit Fruit type: Raspberry Aggregate fruit Fruit type: Blackberry Aggregate fruit Fruit type: Orange Simple fruit Fruit type: Apple Simple fruit Examples of the fruit group: Pome Apple, pear Examples of the fruit group: Drupe Cherry, peach, plum, coconut Examples of the fruit group: Berry Banana, tomato, grape Examples of the fruit group: Hesperidium Orange, lemon, grapefruit Examples of the fruit group: Pepo Cucumber, squash, watermelon Examples of the fruit group: Legume Bean, pea, honey locust Examples of the fruit group: Follicle Milkweed, larkspur Examples of the fruit group: Silique Shepherd's Purse, mustard Examples of the fruit group: Winged Schizocarp Maple Examples of the fruit group: Schizocarp Dill, carrot Examples of the fruit group: Nut Hazel nut, hickory, walnut, acorn Examples of the fruit group: Grain (Caryopsis) All grasses Examples of the fruit group: Achene Smartweed, sunflowers Dehiscent In dehiscent fruits, the tissues of the mature ovary wall break open, freeing the seeds Indehiscent In Indehiscent fruits, the seeds remain in the fruit after the fruit has been shed from the parent plant An example of an embryo with large cotyledons and little endosperm Lima beans An example of an embryo with small cotyledons and much endosperm Castor beans Scutellum In grasses, the single massive cotyledon Coleoptile The protective sheath covering the early shoot Coleorhiza The protective sheath covering the early root Aleurone layer A special layer of cells surrounding the endosperm Normal germination requires: Proper temperature, water, oxygen, and sometimes light Dormant If a seed does not germinate given proper conditions Reasons for seed dormancy Seed coat impervious to water and/or oxygen; seed has an immature embryo; seed has chemical inhibitors in the seed coat that must be leached out. Scarification Breaching the seed coat physically or chemically so that water and oxygen can get in Three stages of plant embryology Ball stage, heart-shaped stage, bending cotyledons stage Three distinct tissue layers differentiate early in embryo development Protoderm, Procambium, Ground Meristem Protoderm Will become the plant's epidermis (dermal tissues) Procambium Will become the primary xylem and phloem (vascular tissues) Ground Meristem Will become the pith, cortex, and associated stem and root structures (ground tissues) Plant organs Roots, Stems, Leaves, Flowers/Fruits Simple tissues Have only one cell type (parenchyma, collenchyma, meristematic) Complex tissues Composed of two or more cell types (vascular, dermal, ground) Meristematic cells Found in meristems (root & shoot), cambial layers, and buds. Function is cell division. Parenchyma cells Thin cellulose cell walls; usually with a large vacuole; function as storage or packing cells. Common in the pith and cortical layers, wood rays, petals. Chlorenchyma cells Large parenchyma cells with chloroplasts. Found in the leaves and in some stems. Major function is photosynthesis. Collenchyma cells Used for temporary support. Cell walls have extra cellulose in the corners. Example: celery ribs Sclerenchyma cells Have thick secondary cell walls of lignin, and are dead at maturity. Include fibers, sclereids, tracheids, and vessel elements. Fibers Long, narrow cells with thick walls and a small lumen; Used for support in woody tissues or for support in vascular bundles and herbaceous stems; not found in conifer wood. Conifer wood is used for lumber because It lacks Fiber cells, which would make the wood very hard. Sclereids Irregular cells with thick walls; function primarily for protection. The stone cell is a special type of this cell Sclereid This gives pears their gritty texture Stone cells Tracheids Water conducting cells of the xylem in gymnosperms, ferns, and fern allies; Cells have closed end walls; May have complex pits through which water moves from cell to cell Vessel Elements Water conducting cells of the xylem in angiosperms and gnetophytes; have open end walls; are short and squat cells one on top of another, forming vessel tubes for conduction Sieve Tube Members Tall, thin cells with only primary cellulose cell walls; Living cells but lack a nucleus at maturity; Part of the phloem tissue Companion Cells Long, thin cells, with a nucleus directly adjacent to each sieve tube member; STM and CC are derived from the same initial; Responsible for loading and unloading of substances from the STM in the phloem Tap root systems are found most commonly in Dicots Fibrous root systems are found most commonly in Monocots These consist of a prominent root and smaller branch roots Tap root systems These consist of many similar sized roots in an extensive network Fibrous root systems Functions of root systems Anchorage, Storage, Absorption, Conduction, Reproduction (occasionally) The Casparian Strip The suberized layer of cells forces water to move through the cells and not the cell walls Endodermis Innermost layer of the cortex; functions in water regulation; Casparian Strip. Pericycle Source of cells for formation of branch (lateral) roots Branch roots have this type of growth Endogenous Protoxylem First to mature in the root Metaxylem Last to mature in the root Monocots have this unique root structure Siphonostele Examples of tap roots Radish, jicama, carrots Examples of fascicled storage roots Yams, sweet potatoes, cassava Examples of prop roots Corn Examples of aerial roots Spanish moss, orchids Example of reproduction by tree roots Aspen Fascicled roots Are bundles of storage roots Apical meristem A shoot tip; composed of tunica and corpus layers Tunica layer Layer in the apical meristem that gives rise to protoderm Corpus layer Layer in the apical meristem that gives rise to procambium and ground meristem Axillary buds Lateral buds that give rise to stem branches Axillary buds have this type of development Exogenous Monocot stems have scattered vascular bundles, known as Atactostele Tendril Stem modification used for attachment; Ivy is an example Ivies have this kind of stem modification Tendrils Stolon Stem modification that grows horizontally along the ground, that may form adventitious roots Runner Same as a stolon; stem modification that grows horizontally along the ground, that may form adventitious roots Cladophyll Stem modification used for photosynthesis; they resemble leaves. Thorn Stem modification that is a modified branch Prickle Stem modification that is an epidermal outgrowth; Rose is an example Roses have this kind of stem modification Prickle Spine A modified leaf Tuber An underground stem; examples are white potato Eye of the potato is actually this Axillary bud White and russet potatoes are examples of this stem modification Tuber If a pattern is present in branching, we say this is present Phyllotaxis Roots always grow downward. This is called: Positively gravitropic Stems grow upward. This is called: Negatively gravitropic Roots have these types of steles Protostele (dicot) or siphonstele (monocot) Stems have these types of steles Eustele (dicot) or atactostele (monocot) These have an endodermis Roots These lack an endodermis Stems These have vascular cambia from fascicular and interfascicular cambia Stems These have vascular cambia from pericycle and cambium Roots Type of xylem and phloem found in roots Radial xylem and phloem Type of xylem and phloem found in stems Collateral xylem and phloem Commonly known as pine Pinus Commonly known as arbor vitae Thuja Commonly known as hemlock Tsuga Commonly known as spruce Picea Commonly known as Junipers Juniperus Commonly known as red cedar Juniperus Commonly known as Douglas Fir Pseudotsuga Commonly known as fir Abies Commonly known as larch Larix Commonly known as yew Taxus Commonly known as sago palm Cycas Commonly known as ginkgo Ginkgo biloba Commonly known as maidenhair tree Ginkgo biloba Commonly known as tropical vines Gnetum Commonly known as Mormon Tea Ephedra Pinus belongs to this division Coniferophyta Tsuga belongs to this division Coniferophyta Picea belongs to this division Coniferophyta Juniperus belongs to this division Coniferophyta Pseudotsuga belongs to this division Coniferophyta Abies belongs to this division Coniferophyta Larix belongs to this division Coniferophyta Taxus belongs to this division Coniferophyta Cycas belongs to this division Cycadophyta Zamia belongs to this division Cycadophyta The only cycad native to the U.S. Zamia Ginkgo biloba belongs to this division Ginkgophyta Gnetum belongs to this division Gnetophyta Ephedra belongs to this division Gnetophyta Welwitschia belongs to this division Gnetophyta The study of tree rings Dendrochronology The first group to evolve true megaphyllous leaves Ferns (pterophyta) Live fern gametophytes Prothallia Gymnosperms are commonly known as The naked seed plants Each of these in pines usually bears two ovules Ovuliferous scales