FLOWERS

Overview of Plant Kingdom

  • Classification of plants includes several categories:

    • Algae

    • Bryophytes

    • Pteridophytes

    • Angiosperms

    • Gymnosperms

Characteristics of Major Plant Groups

Non-Vascular Plants (Cryptogams)

  • Lack true roots, stems, or leaves.

  • Examples include:

    • Algae (Chlorophyta)

    • Mosses and liverworts (Bryophyta)

Vascular Plants (Phanerogams)

  • Have roots, stems, and leaves.

  • Include:

    • Pteridophytes (Ferns and Horsetails)

    • Gymnosperms (Conifers, Ginkos, Cycads)

    • Angiosperms (Flowering plants)

Gymnosperms vs. Angiosperms

Gymnosperms (Non-Flowering Plants)

  • Produce seeds that are unenclosed (naked).

  • Examples:

    • Conifers (Pinophyta)

    • Ginkos (Ginkgophyta)

    • Cycads (Cycadophyta)

Angiosperms (Flowering Plants)

  • Produce seeds enclosed within an ovary.

  • Distinct lifecycle patterns:

    • Seasonal life cycles

    • Includes hardwood and softwood types.

Structure and Function of Flowers

Parts of a Flower

  1. Pistil (Female part)

    • Stigma: Sticky tip for pollen attachment.

    • Style: Connects stigma and ovary.

    • Ovary: Contains ovule.

  2. Stamen (Male part)

    • Anther: Produces pollen.

    • Filament: Supports the anther.

  3. Non-Reproductive Parts

    • Sepals: Protect the developing flower.

    • Petals: Aid in pollination by attracting pollinators.

Reproduction in Angiosperms

  • Steps:

    1. Pollination: Pollen reaches the stigma.

    2. Fertilization: Sperm fertilizes the egg within the ovule.

    3. Fruit Development: The ovary becomes a fruit.

    4. Seed Dispersal: Seeds are dispersed by animals or wind.

Types of Angiosperms

Monocots

  • Characteristics:

    • One cotyledon.

    • Floral parts in threes.

    • Examples: Grass, corn, lilies.

Dicots

  • Characteristics:

    • Two cotyledons.

    • Floral parts in fours or fives.

    • Examples: Roses, maple trees, apples.

Pollination Methods

Self-Pollination

  • Pollination occurs within the same flower or plant.

Cross-Pollination

  • Pollen is transferred to a different plant's flower.

Types of Flowers

Unisexual Flowers

  • Have either male or female reproductive organs, but not both.

    • Example: Papaya (Male and Female flowers)

Bisexual Flowers

  • Contain both male and female reproductive organs.

Flower Types

Pistillate Flower

  • Contains female parts, lacks stamens.

  • Main components:

    • Carpels (style, stigma, ovary)

Staminate Flower

  • Contains only male reproductive parts.

  • Main components:

    • Stamen (filament, anther)

Other Plant Reproduction Methods

Asexual Reproduction

  1. Budding in Hydra

  • New hydra forms from a parent hydra.

  1. Cutting

  • Fragmentation leads to new plant.

  1. Grafting

  • Combining parts from two plants (scion and stock).