Plant Structure and Function

Roots

• Underground plant structures responsible for:
  • Absorbing water and nutrients from the soil
  • Anchoring the plant in place
  • Storing food and nutrients
• Types of roots:
  • Taproot: single, thick main root (e.g., carrots)
  • Fibrous roots: many small roots (e.g., grasses)
  • Adventitious roots: roots that grow from stems or leaves (e.g., ivy)

Stems

• Above-ground plant structures responsible for:
  • Supporting leaves and flowers
  • Transporting water, nutrients, and sugars between roots and leaves
  • Providing a framework for plant growth
• Types of stems:
  • Herbaceous stems: non-woody, soft stems (e.g., herbs)
  • Woody stems: hard, rigid stems (e.g., trees)

Leaves

• Organs responsible for:
  • Photosynthesis: converting sunlight into energy
  • Gas exchange: exchanging oxygen and carbon dioxide
  • Transpiration: releasing water vapor
• Leaf structures:
  • Blade (lamina): the flat part of the leaf
  • Petiole: the stalk connecting the leaf to the stem
  • Veins: networks of tubes that transport water and nutrients

Flowers

• Reproductive structures responsible for:
  • Producing seeds and fruits
  • Attracting pollinators (e.g., bees, butterflies)
  • Ensuring genetic diversity
• Flower parts:
  • Sepals: green, leaf-like structures that protect the bud
  • Petals: colorful structures that attract pollinators
  • Stamens: male reproductive organs (anthers and filaments)
  • Carpels: female reproductive organs (stigma, style, and ovary)

Fruits and Seeds

• Fruits: mature ovaries containing seeds
• Seeds: reproductive structures containing embryonic plants
• Functions:
  • Dispersal: spreading seeds to new locations
  • Protection: protecting the embryo from environmental stress
  • Nutrition: providing nutrients for seedling growth

Roots

• Absorb water and nutrients from the soil and anchor the plant in place
• Store food and nutrients for later use
• Taproot: single, thick main root (e.g., carrots)
• Fibrous roots: many small roots (e.g., grasses)
• Adventitious roots: roots that grow from stems or leaves (e.g., ivy)

Stems

• Support leaves and flowers
• Transport water, nutrients, and sugars between roots and leaves
• Provide a framework for plant growth
• Herbaceous stems: non-woody, soft stems (e.g., herbs)
• Woody stems: hard, rigid stems (e.g., trees)

Leaves

• Perform photosynthesis, converting sunlight into energy
• Exchange oxygen and carbon dioxide through gas exchange
• Release water vapor through transpiration
• Consist of a blade (lamina), petiole, and veins
• Veins: networks of tubes that transport water and nutrients

Flowers

• Produce seeds and fruits
• Attract pollinators (e.g., bees, butterflies)
• Ensure genetic diversity
• Consist of sepals, petals, stamens, and carpels
• Stamens: male reproductive organs (anthers and filaments)
• Carpels: female reproductive organs (stigma, style, and ovary)

Fruits and Seeds

• Fruits: mature ovaries containing seeds
• Seeds: reproductive structures containing embryonic plants
• Facilitate dispersal, spreading seeds to new locations
• Protect the embryo from environmental stress
• Provide nutrients for seedling growth