Plant Kingdom Notes

Plant Kingdom

Kingdom Plantae Characteristics

  • Multi-cellular: Plants are composed of multiple cells.
  • Autotrophic: They produce their own food through photosynthesis.
  • Eukaryotic: Their cells contain a nucleus and other complex organelles.
  • Cell Walls: Made of cellulose, providing structural support.
  • Food Storage: Store food in the form of starch.
  • Chlorophyll & Vacuole: Contain chlorophyll for photosynthesis and large vacuoles for storage and support.
  • Reproduction: Can reproduce sexually and/or asexually.

Plant Classification Overview

  • Non-Vascular Plants (Bryophytes)
    • Liverworts (Marchantiophyta)
    • Hornworts (Anthocerotophyta)
    • Mosses (Bryophyta)
  • Vascular Plants (Tracheophytes)
    • Spore-Producing Plants (Pteridophytes)
      • Club Mosses (Lycopodiophyta)
      • Horsetails (Equisetophyta)
      • Ferns (Pteridophyta)
    • Seed-Producing Plants (Spermatophytes)
      • Non-Flowering Plants (Gymnosperms)
        • Conifers (Pinophyta)
        • Cycads (Cycadophyta)
        • Ginkgo (Ginkgophyta)
      • Flowering Plants (Angiosperms)
        • Plants with One Seed Leaf (Monocots)
        • Plants with Two Seed Leaves (Dicots)

Bryophytes (Non-Vascular Plants)

  • Lack specialized vascular tissues for transporting water and nutrients.
  • Three divisions:
    • Hepaticophyta (Liverworts)
    • Anthocerophyta (Hornworts)
    • Bryophyta (Mosses)

Water and Mineral Transportation in Plants

  • Water Absorption: Root hairs absorb water and minerals from the soil.
  • Nutrient Uptake: Ions like K^+, Ca^{2+}, Cu^{2+}, and Mg^{2+} are absorbed from the soil.
  • Role of H^+$: Hydrogen ions (H+) facilitate mineral uptake.
  • Carbonic Acid: Formed from water and carbon dioxide (H2O + CO2 \rightarrow H2CO3), which then dissociates into bicarbonate and hydrogen ions (H2CO3 \rightarrow HCO_3^- + H^+$$).

Bryophyte Reproduction

  • Haploid (n) and Diploid (2n) Stages: Alternation of generations.
  • Spores: Released for dispersal; develop into protonemata.
  • Protonemata: Develop "buds" that grow into gametophores.
  • Gametophytes:
    • Male gametophytes produce antheridia and sperm.
    • Female gametophytes produce archegonia and eggs.
  • Fertilization: Sperm fertilizes the egg within the archegonium to form a zygote (2n).
  • Sporophyte Development:
    • Zygote develops into a young sporophyte.
    • Mature sporophyte consists of a foot, seta, and sporangium (capsule).
    • Sporangium contains spores formed by meiosis.
  • Asexual Reproduction: Gemmae.

Liverworts

  • Nonvascular: Lack vascular tissue.
  • Spore Reproduction: Reproduce by spores.
  • Alternation of Generations: Sporophyte is attached to the dominant gametophyte.
  • Gametophyte Dominance: Green, leafy gametophyte is the dominant stage.
  • Water Dependence: Need abundant water for fertilization.
  • Habitat: Grow on moist soil, rocks, or other moist surfaces.
  • Asexual Reproduction: Gemmae or new branches.
  • Sexual Reproduction: Haploid spores.

Hornworts

  • Small, Nonvascular Bryophytes: Similar to liverworts but with distinct sporophytes.
  • Gametophyte Dominance: Leafy gametophyte is dominant.
  • Archegonia & Antheridia: Form inside the plant.
  • Sporophytes: Zygotes develop into long, horn-shaped sporophytes.
  • Photosynthesis: Sporophytes are capable of photosynthesis.
  • Nutrient Dependence: Sporophytes obtain nutrients from the gametophyte.

Moss Graffiti

  • Materials: Moss, buttermilk/yogurt, water/beer, sugar, blender, paintbrush, container.
  • Steps:
    1. Gather moss.
    2. Wash dirt off moss roots.
    3. Break up moss and place in blender.
    4. Add 2 cups buttermilk/yogurt, 2 cups water/beer, and 1/2 teaspoon of sugar. Blend until smooth.
    5. Paint your graffiti.
  • Maintenance: Spray water to keep art alive.
  • Best Surfaces: Porous surfaces like brick and stones.
  • Environment: Moderate sunlight and moisture; spring and fall are best seasons.
  • Removal: Spray with lime juice.

Pteridophyta (Ferns)

  • Vascular System: Presence of a vascular system (xylem and phloem).
  • Dominant Sporophyte Stage: Sporophyte is the dominant stage in the life cycle.
  • Spore Dispersal: Dispersal through spores.
  • Fronds and Sori: Ferns produce leaf-like fronds with spore-producing structures called sori on the underside.

Vascular Tissue

  • Xylem: Conducts water and dissolved minerals upward from the roots.
  • Phloem: Conducts sucrose and hormones throughout the plant.
  • Sporophyte Development: Develops in the sporophyte but not the gametophyte.
  • Cuticle and Stomata: Also found in land plants for protection and gas exchange.

Fern Characteristics

  • Specialized Transport Tissues: Xylem & phloem.
  • Alternation of Generations: Sporophyte and gametophyte stages.
  • Dominant Sporophyte: The sporophyte stage is dominant.
  • Spore Reproduction: Reproduce by spores.

Fern Habitats and Reproduction

  • Habitat Range: Terrestrial, aquatic, arboreal tree ferns, epiphytic.
  • Asexual Reproduction: Rhizomes (underground stems).
  • True Roots, Stems, and Leaves: Dominant sporophyte has true roots, stems, and leaves.
  • Underground Roots and Stems: Roots and stems are typically underground.
  • Fronds: Leaves called fronds are found above ground, attached to a stem-like petiole.

Leaf Types

  • Tropophyll: Function is for photosynthesis; does not produce spores.
  • Sporophyll: Produces spores.
  • Heterophyll: Has two leaves with different sizes and shapes.
  • Homophyll: Has leaves with the same size and shape.

Spore Types

  • Homospore (Isospore): Produce one type of spore with the same size and shape. Example: Lycopodium sp.
  • Heterospore (Anisospore): Produce two different types and sizes of spores. Example: Selaginella sp., Marsilea sp.
  • Mixed-spore: Produces the same size of spore, but different types (male and female). Example: Equisetum debile.

Lycophytes and Pterophytes

  • Lycophytes:
    • Worldwide distribution, abundant in tropics.
    • Lack seeds.
    • Resemble true mosses superficially.
    • Sporophyte dominant.
  • Pterophytes:
    • Phylogenetic relationships among ferns and their relatives are still being sorted out.
    • All form antheridia and archegonia.
    • All require free water for flagellated sperm.

Whisk Ferns and Horsetails

  • Whisk Ferns:
    • Found in tropics.
    • Sporophyte consists of evenly forking green stems without true leaves or roots.
    • Some gametophytes develop elements of vascular tissue.
  • Horsetails:
    • 15 living species (Equisetum).
    • Sporophyte consists of ribbed, jointed photosynthetic stems arising from branching rhizomes with roots at nodes.
    • Silica deposits in cells (scouring rush).

Fern Life Cycle

  • Differences from Mosses: Fern life cycle shows greater development, independence, and dominance of the sporophyte.
  • Gametophyte Lacks Vascular Tissue: Gametophyte does not have vascular tissue.
  • Rhizomes: Sporophytes have rhizomes.
  • Fronds: Develop at the tip of the rhizome as tightly rolled-up coils (“fiddleheads”).

Fern Reproduction

  • Sori: Produce distinctive sporangia in clusters called sori on the back of fronds.
  • Meiosis: Diploid spore mother cells in sporangia produce haploid spores by meiosis.
  • Gametophyte Development: Spores germinate into a gametophyte with rhizoids but no true roots and no vascular tissue.
  • Flagellated Sperm: Requires water for fertilization.

Fern Structures and Gametophyte Stage

  • Fiddleheads: Newly forming fronds must uncurl.
  • Sori: Spore cases found on the underside of fronds.
  • Prothallus: Spores land on moist soil and germinate into a prothallus.
  • Gametophyte Stage: The prothallus starts the gametophyte stage.
  • Heart-Shaped Gametophyte: Gametophyte is heart-shaped and short-lived.
  • Antheridia and Archegonia: Male antheridia & female archegonia grow on the gametophyte.
  • Fertilization: Sperm swims to egg to fertilize.

Parts of the Fern Sporophyte

  • Frond: The main leaf.
  • Pinnae: Leaflets of the frond.
  • Stipe: The stalk that supports the frond.
  • Rhizome: Underground stem.

Key Terms in Fern Reproduction

  • Sporophyte: The diploid, spore-producing plant.
  • Spore: Haploid reproductive cell.
  • Sporangium: Structure where spores are produced.
  • Antheridium: Male reproductive structure producing sperm.
  • Zygote: Diploid cell resulting from fertilization.
  • Gametophyte: Haploid, gamete-producing plant.
  • Sperm: Male gamete.
  • Archegonium: Female reproductive structure containing the egg.
  • Egg: Female gamete.

Uses for Ferns

  • Erosion Prevention: Help prevent soil erosion.
  • Food: Fiddleheads are eaten as food.
  • Ornamental Plants: Used as ornamental plants for yards and homes.
  • Coal Deposits: Helped form coal deposits millions of years ago.

Seed Plants: Gymnosperms and Angiosperms

  • Seed Development: Ability to form seeds led to dominance of photosynthetic organisms on land.
  • Two Groups: Gymnospermae and Angiospermae.

Seed Structure

  • Integument: Embryo protected by integument, which hardens into a seed coat.
  • Megasporangium: Divides meiotically inside ovule to produce haploid megaspore.
  • Megaspore Function: Megaspore produces egg that combines with sperm to form zygote.
  • Food Supply: Also contains food supply for embryo.

Gametophytes in Seed Plants

  • Two Kinds of Gametophytes: Male (micro-) and female (mega-) gametophytes.
  • Male Gametophytes (Pollen Grains):
    • Dispersed by wind or a pollinator.
    • No need for water.
  • Female Gametophytes:
    • Develop within an ovule.
    • Enclosed within diploid sporophyte tissue in angiosperms.

Embryo and Seed Coat

  • Embryo: Early development stage of a sporophyte plant.
  • Nutrient Supply: The seed’s food supply provides nutrients to the embryo as it grows.
  • Seed Coat: Surrounds and protects the embryo; prevents drying out; can be specialized for dispersal.

Gymnosperms: "Naked Seeds"

  • Description: Plants with ‘naked seeds’ (cone plants).
  • Seed Placement: Bear their seeds directly on the surfaces of cones.
  • Examples: Conifers, pines, spruces, cycads, ancient ginkgoes, and gnetophytes.

Cones: Seed-Bearing Structures

  • Function: Seed-bearing structures of gymnosperms.

Gymnosperm Characteristics

  • Unenclosed Seeds: Gymnosperms have seeds that are not enclosed (naked seeds).
  • Cone-Bearing Plants: Seeds grow on cones.
  • Leaves: Needle-like leaves.
  • Evergreen: Usually stay green year-round.
  • Pollination: Wind pollinated.
  • Sexual Reproduction: Can be monoecious or dioecious.
  • Examples: Pine trees & evergreens.

Gymnosperm Reproduction

  • Microspores: Develop into pollen grains in pollen-bearing cones.
  • Megaspores: Develop within ovulate (seed-bearing) cones.
  • Pollination: Pollen tube grows towards the megaspore.
  • Fertilization: Sperm fertilizes the egg (15 months after pollination).
  • Zygote Development: Zygote develops into a seedling.
  • Seed Structure: Embryo embedded in megagametophyte.

Gnetinae

  • Vessels in Xylem: The only Gymnospermae with vessels in their xylem.
  • Dioecious: Separate male and female plants.
  • Example: Melinjo.

Cycadinae

  • Short Stem & Non-branching: Has a short stem and does not branch.
  • Short Growing: Short growing gymnospermae.
  • Young Leaves: Young leaves are rolled (fern-like).
  • Diesis: Dioecious.
  • Example: Cycas rumphii (Pakis haji).

Ginkgoinae

  • Tree Form: Plants that form trees, up to 50m tall.
  • Branches: Has branches.
  • Flagellated Sperm: Possesses flagellated sperm.
  • Dioecious: Separate male and female plants.
  • Example: Ginkgo biloba.

Coniferae

  • Habitat: Can live in sub-tropic and tropic regions.
  • Leaves: Needle-like and evergreen.
  • Economic Importance: Conifers are sources of important products like timber, paper, resin, and taxol (anti-cancer).
  • Monoecious: Both male and female cones on the same plant.
  • Example: Pinus merkusii.

Angiosperms: Flowering Plants

  • Description: Flowering plants.
  • Seed Enclosure: Bear their seeds within a layer of tissue that protects the seed.
  • Examples: Grasses, flowering trees, shrubs, wildflowers.

Flowers: Seed-Bearing Structures of Angiosperms

  • Function: Seed bearing structures of angiosperms

Angiosperm Characteristics

  • Success: Most successful group of plants.
  • Co-evolution: Co-evolved with insects to improve pollination.
  • Seed Enclosure: Seeds are enclosed, usually in a fruit.
  • Pollination: Most are pollinated by birds & bees.
  • Growing Seasons: Have finite growing seasons.
  • Examples: Grasses, tulips, oaks, dandelions.
  • Two Main Groups: Monocots & Dicots.

Flower Structure

  • Specialized Shoot: A flower is a specialized shoot with modified leaves.
  • Sepals: Enclose the flower.
  • Petals: Brightly colored and attract pollinators.
  • Stamens: Produce pollen.
  • Carpels: Produce ovules.

Pollination

  • Definition: The transfer of pollen from the male gametophyte to the female gametophyte.

Carpel Structure

  • Stigma: Receives pollen.
  • Style: Connects stigma to ovary.
  • Ovary: Contains ovules.
  • Ovule: Contains the megasporocyte.
  • Micropyle: Opening in the ovule for pollen tube entry.

Megaspore Creation

  • Megasporocyte: Undergoes meiosis to produce a megaspore.

Female Gametophyte Creation

  • Megaspore Development: Develops into the female gametophyte.
  • Embryo Sac: Mature female gametophyte, containing:
    • Antipodals
    • Polar nuclei
    • Synergids
    • Egg nucleus/cell

Double Fertilization in Angiosperms

  • Two Sperm Cells: One sperm unites with the egg, and another unites with the polar nuclei.
  • Zygote Formation: One sperm (n) unites with egg (n) to form diploid zygote (2n).
  • Endosperm Formation: Other sperm (n) unites with the two polar nuclei to form the triploid endosperm.

Seed and Fruit Development

  • Seed Coat: Protects the seed.
  • Endosperm: Provides nutrients to the embryo.
  • Embryo: Develops into the new plant.
  • Fruit: Develops from the ovary.

Double Fertilization Significance

  • Zygote: (n) unites with egg (n) to form diploid zygote.
    • New sporophyte.
  • Endosperm: Other sperm (n) unites with the two polar nuclei to form the triploid endosperm.
    • Provides nutrients to embryo.

Types of Pollination

  • Self-Pollination (Autogamy): Pollen falls to stigma from the same flower.
  • Neighborhood Pollination (Geitonogamy): Pollen falls to pistil head from another flower on the same plant.
  • Cross-Pollination (Allogamy): Pollen falls to stigma from another flower of another plant of the same species.
  • Bastard Pollination (Hybridogamy): Pollen falls to stigma from another flower of another plant of a different variety.

Pollination Factors

  • By Animal (Entogamy): Pollination by insects.
  • Ornithogamy: Pollination by birds.
  • Kiroptogamy: Pollination by bats.
  • Malacogamy: Pollination by snails.

Pollination Strategies

  • Color Attraction: Birds are attracted to red flowers; bees see colors humans cannot.
  • Nocturnal Pollination: Moth-pollinated flowers are white and bloom at night.
  • Odor Attraction: Many insects are attracted to odors (e.g., rotting meat smell).
  • Flower Shape: Shaped to allow access only to specific pollinators (e.g., hummingbird flowers).
  • Wind Pollination: Wind-pollinated flowers are small, lack petals, and do not produce nectar.

Seed Dispersal Mechanisms

  • (a) Wind Dispersal: Wings enable maple fruits to be carried by the wind.
  • (b) Animal Dispersal: Seeds within berries are dispersed in animal feces.
  • (c) Hitchhiking: Barbs of cockleburs facilitate seed dispersal by attaching to animals.

Plant Structure Overview

  • Flower: Reproductive structure.
  • Fruit: Develops from the pistil and contains seeds.
  • Shoot: Includes the stem, leaves, and flowers.
  • Root: Anchors the plant and absorbs water and nutrients.
    • Primary root.
    • Lateral roots.
    • Root hairs.
    • Root tip.
    • Root cap.

Monocots vs. Dicots

  • Cotyledons: Monocots have one cotyledon; dicots have two.
  • Floral Parts: Monocots have floral parts in multiples of three; dicots in fours or fives.
  • Leaf Veins: Monocots have parallel leaf veins; dicots have netlike veins.
  • Pollen Grains: Monocots have one pore or furrow; dicots have three pores or furrows.
  • Vascular Bundles (Stem): Monocots have scattered vascular bundles; dicots have bundles arranged in a ring.

Monocot Characteristics

  • One Seed Leaf (Cotyledon)
  • Parallel Veins on Leaves.
  • 3 Part Symmetry for flowers
  • Fibrous Roots
  • Vascular Tissue Scattered

Dicot Characteristics

  • Two Seed Leaves (Cotyledons)
  • Net Veins on Leaves
  • Flowers Have 4-5 Parts
  • Taproots
  • Vascular Tissue Arranged in a Ring

Classes of Monocots

  • Graminae: Rice, Corn, Bamboo, Grass, Sugarcane, Wheat.
  • Palmae: Coconut, Rattan, Oil Palm, Aren, Salacca.
  • Zingiberaceae: Turmeric, Ginger, Galangal.
  • Bromeliaceae: Pineapple.
  • Musaseae: Banana, Ornamental Banana, Fan Banana.
  • Orcidaceae: Moon Orchid, Orchids that grow in Papua's forests, Tiger Orchid.

Classes of Dicots

  • Euhorbiaceae: Cassava Tree, Castor Oil Plant, Rubber Tree, Puring.
  • Leguminosae: Mimosa pudica, Petai, Flamboyant, Soybean, Peanut.
  • Solanaceae: Eggplant, Chili, Tomato, Jimsonweed.
  • Rutaceae: Sweet Orange, Pomelo.
  • Malvaceae: Hibiscus.
  • Mirtaceae: Clove, Guava, Water Guava.
  • Compositae: Sunflower, Dahlia, Chrysanthemum.

Summary of Monocot vs. Dicot features

  • Vascular Bundle Arrangement:
    • Monocots: Scattered vascular bundles in stem x-section.
    • Dicots: vascular bundles arranged in a circle in stem x-section.
  • Leaf Venation:
    • Monocots: Parallel.
    • Dicots: Netted.
  • Flowers:
    • Monocots: floral parts in multiples of 3.
    • Dicots: floral parts in multiples of 4 or 5.
  • Seeds:
    • Monocots: contain one cotyledon.
    • Dicots: contain two cotyledons.
  • Stems:
    • Monocots: vascular bundles are scattered.
    • Dicots: vascular bundles arranged in a circle.
  • Leaves:
    • Monocots: long tapering blades with parallel venation.
    • Dicots: broad to narrow leaves with netted venation.