Plants

• Flower - purpose is for sexual reproduction of plants. Are produced by angiosperm, not found in gymnosperm.
• Parts of a Flower

  1. Sepal
  2. Petal
  3. Stamen
  4. Pistil
• Sepal - green leaf-like structure that protects the petals.
• Petals - modified colorful leaves. Collectively called the corolla.
• Stamen - male reproductive part. Filament is the thin salk that holds the anther. Anther is the sac-like structure that produces pollen.
• Pistil -female reproductive part.
• Stigma - sticky tip that collects pollen.
• Style - long stalk that sperm passes through.
• Ovary - at the base and houses the ovules. The ovules then turn into fruit while the ovary turns into fruit.
• Perfect Flower - contains both male and female sex organs, known as bisexual.
• Complete Flower - has all four parts of the flower. (sepals, petals, pistil, and stamen.)
• Complete Flowers are Perfect Flowers. If the petals or sepals are missing, it may still be perfect, given the pistil and stamen.
• Incomplete Flower - Does not have all parts of a flower.
• Flowers are important because they provide nectar to animals, help the transfer of pollen, provide aesthetic/decoration to the surrounding, and provide natural medicine for humans and some animals.
• Pollination - process of transferring pollen grains from the stamen to the stigma. Pollinators aid in pollination.
• Self Pollination - egg cell in ovule is fertilized by sperm from the same flower or another flower of the same plant.
• Cross Pollination - the sperm is from a different plant.
• Fertilization - union of the male gamete (sperm) and female gamete (egg)
• Steps of Fertilization

  1. Pollen grains are transferred from another to stigma
  2. Pollen grains will go down to the style
  3. Contents of pollen (sperm) transferred to the ovule and fertilizes the egg inside it.
  4. Seed is produced and later it will develop into a new plant.
• Germination - process of a plant growing from a seed.
• The steps of Germination:

  1. The absorption of water and internal processes happen.
  2. The seed coat breaks then the roots (radicle) grows down to absorb water.
  3. The first leaves (plumule) start to grow upward. More leaves continue to emerge.
  4. After germination, the plant develops and grows up to maturity. Once mature, the plants are able to produce their own offspring.
• Needs of Seeds for Germination:

  • right temperature
  • right moisture
  • presence of oxygen
  • right light conditions
• Right Temperature

  • generally seeds grow at 25-30 C
  • minimum temperature = lowest temperature the seed can grow.
  • maximum temperature = high temperature
• Right Moisture or Water

  • water allows the swelling of root or seed
• Presence of Oxygen

  • Seeds also need to respire
  • inhale oxygen and exhale carbon dioxide.
• Right Light Condition - some seeds need light while others need complete darkness.
• Imperfect Flower - has one male or female sex organ, known as unisex.