Flowers

• The function of leaves are photosynthesis
• What is the function of the waxy cuticle

  • waterproofing
• Palisade layer

  • photosynthesis
• guard cell

  • window for gas exchange
  • CO2 in, O2 out
• lower epidermis/cuticle

  • skin/barrier
• Xylem vs. phloem

  • xylem: water
  • Phloem: sugar (dissolved in water)
• Functions of stems

  • transports stuff up and down
  • holds leaves into the sun
• process of secondary growth

  • start as a green stem "primary growth"
  • vascular bundles widen
  • bundles attach to a complete ring
  • ≈ 1 per year
  • called vascular cambium
  • both in and out
  • Xylem: in (wood)
  • Phloem: out (bark)
• Flowers

  • reproductive structures of plants
  • Flower = male/female anatomy
  • Seed = "plant baby"
• how flowers reproduce

  1. pollen lands on stigma
  2. pollen tube grows down to an ovule
  3. The male cell swims down and fertilizes the ovule
  4. Pollen + ovule = seed
  5. Maturation
  6. seed matures
  7. ovary grows/swells/ripens (fruit)
• Flower gender

  • Male: stamen
  • Organs: anther, filament
  • Female: pistil
  • Organs: stigma, style, ovary
• Functions

  • Anther: makes pollen, male haploid cell
  • Filament: supports anther
  • Petal: advertisement
  • Sepal: protected bud
  • Stigma: sticky to catch pollen
  • Style: supports stigma
  • Ovary: holds ovules (female haploid cell)