Morphology of Flowering Plants

Morphology of Flowering Plants

Root System

• Consists of primary root (taproot) and secondary roots (lateral roots)
• Functions: anchorage, absorption of water and nutrients, storage of food
• Types of root systems:
  • Taproot system (e.g., carrots, beets)
  • Fibrous root system (e.g., grasses, wheat)

Stem

• Functions: support, transport of water and nutrients, storage of food
• Types of stems:
  • Herbaceous stems (non-woody, die back in winter)
  • Woody stems (permanent, grow in diameter)
• Stem modifications:
  • Thorns (e.g., roses, cacti)
  • Tendrils (e.g., peas, grapes)
  • Underground stems (e.g., potatoes, rhizomes)

Leaf

• Functions: photosynthesis, transpiration
• Leaf structure:
  • Blade (lamina)
  • Petiole (stalk)
  • Venation: arrangement of veins
• Types of leaves:
  • Simple leaves (e.g., maple)
  • Compound leaves (e.g., walnut, horse chestnut)
• Leaf modifications:
  • Spines (e.g., cacti)
  • Bracts (e.g., poinsettia)

Inflorescence and Flowers

• Inflorescence: arrangement of flowers on a stem
• Types of inflorescences:
  • Raceme (e.g., lily of the valley)
  • Corymb (e.g., cauliflower)
  • Umbel (e.g., carrots)
• Flower structure:
  • Sepals (calyx)
  • Petals (corolla)
  • Stamens (androecium)
  • Carpels (gynoecium)
• Types of flowers:
  • Complete flowers (have all four whorls)
  • Incomplete flowers (lack one or more whorls)

Fruit and Seed

• Fruit: mature ovary, containing seeds
• Types of fruits:
  • Simple fruits (e.g., banana)
  • Aggregate fruits (e.g., raspberry)
  • Composite fruits (e.g., pineapple)
• Seed structure:
  • Embryo ( Cotyledon, hypocotyl, radicle)
  • Endosperm (nutrient-rich tissue)
  • Seed coat

Morphology of Flowering Plants

Root System

• Primary root (taproot) and secondary roots (lateral roots) make up the root system
• Functions: anchorage, absorption of water and nutrients, and storage of food
• Taproot system examples: carrots, beets
• Fibrous root system examples: grasses, wheat

Stem

• Functions: support, transport of water and nutrients, and storage of food
• Herbaceous stems are non-woody and die back in winter
• Woody stems are permanent and grow in diameter
• Stem modifications: thorns (e.g., roses, cacti), tendrils (e.g., peas, grapes), and underground stems (e.g., potatoes, rhizomes)

Leaf

• Functions: photosynthesis and transpiration
• Leaf structure consists of: blade (lamina), petiole (stalk), and venation (arrangement of veins)
• Simple leaves: single blade, e.g., maple
• Compound leaves: multiple blades, e.g., walnut, horse chestnut
• Leaf modifications: spines (e.g., cacti), bracts (e.g., poinsettia)

Inflorescence and Flowers

• Inflorescence: arrangement of flowers on a stem
• Raceme: flowers on a stem, e.g., lily of the valley
• Corymb: flowers on a stem, e.g., cauliflower
• Umbel: flowers on a stem, e.g., carrots
• Flower structure: sepals (calyx), petals (corolla), stamens (androecium), and carpels (gynoecium)
• Complete flowers: have all four whorls
• Incomplete flowers: lack one or more whorls

Fruit and Seed

• Fruit: mature ovary containing seeds
• Simple fruits: single ovary, e.g., banana
• Aggregate fruits: multiple ovaries, e.g., raspberry
• Composite fruits: multiple ovaries and flowers, e.g., pineapple
• Seed structure: embryo (cotyledon, hypocotyl, radicle), endosperm (nutrient-rich tissue), and seed coat