Science (cycles)

• Asexual reproduction


  Reproduction without fertilisation
• Non-flowering plants


  • Do not produce seeds
  • Usually reproduce from spores
• Spore reproduction in non-flowering plants

  1. Spores are found in spore bags

  2. Spore bags located on underside of mature leaves or at ends of stalks

  3. Spores are tiny and can only be examined under a microscope

  4. Spores are dispersed by the wind because they are light

  5. Spores will germinate and grow into new plants when conditions are favourable
• All plants do not reproduce from seeds
• A microscope allows us to see objects that are too small to be seen with the naked eye
• Only flowering plants reproduce from seeds, non-flowering plants reproduce from spores
• Germination


  The first stage in the development of a plant from a seed
• Seeds need not germinate immediately after they are formed
• Some seeds can remain dormant into not growing for a long time, until the conditions are favourable for them to germinate
• Conditions for seed germination

  • Sufficient air (oxygen)
  • Water
  • Warmth (right temperature)
• A seed does not need light to germinate. Thus, it can germinate in the dark
• Root growth


  Indicates that the seed has germinated
• Germination of a seed

  1. Root appears first

  2. Shoot appears after the root

  3. First leaves of the shoot open

  4. Young plant can carry out photosynthesis to make its own food
• Growth of a seed


  • Seed
  • First root appears
  • First shoot appears
  • First leaves are formed
  • Young plant grows
  • Adult plant with flowers
• The germination of a seed is part of the life cycle of a plant. After a seed has germinated, it continues to grow to complete its life cycle
• Water cycle


  A cycle that ensures a continuous supply of fresh water through evaporation and condensation of water for all living organisms to survive, ensuring the continuity of their kind
• Water cycle


  1. Water bodies gain heat

  2. Evaporation forms water vapor

  3. Water vapor condenses to form clouds

  4. Precipitation (raining)

  5. Rain returns to water bodies
• Evaporation


  Water gains heat from the surrounding air or surrounding air loses heat to the water
• Condensation


  Water vapor loses heat to the surrounding air or surrounding air gains heat from the water vapor
• Clouds are made up of tiny water droplets, not gases
• Precipitation (raining) involves no heat transfer
• The water cycle is a continuous cycle that repeats itself
• Terrarium


  A jar with a plant inside, where the water cycle occurs on a small scale - water evaporates from the moist soil, condenses on the lid, and rains back down into the soil
• Water cycle in a terrarium

  1. Water in moist soil gains heat from the sun and evaporates

  2. Water vapor condenses on the cooler lid

  3. Condensed water droplets fall back into the soil as "rain"
• Plants lose water through transpiration, the process of losing water vapor through their stomata
• Flower parts


  Male parts: Anther, Filament

  Female parts: Stigma, Style, Ovary, Ovule
• Anther


  Produces and stores pollen grains
• Filament


  Holds the anther upright
• Stigma


  Receives the pollen grains in pollination
• Style


  Connects the stigma to the ovary and allows the pollen tube to grow downwards
• Ovary


  Contains the ovules and develops into a fruit after fertilization
• Ovule


  Contains the egg and develops into seeds
• Pollination


  Transfer of pollen grains from the anther to the stigma of a flower of the same species
• Fertilization


  The process when the male reproductive cell in the pollen grain fuses with the female reproductive cell in the ovule
• After fertilization


  The ovary develops into a fruit and the ovules develop into seeds
• Tomatoes are fruits, not vegetables, because they contain seeds
• Lady's fingers are also fruits, not vegetables, because they contain seeds
• Importance of fruits


  • Protect the seeds

  Ensure continuity of the plant species

  Have special characteristics that aid in seed dispersal
• After fruit formation, the petals, anthers, filaments, stigma and style wither and drop off
• Even if the stigma is removed, the flower can still develop into a fruit if it was already pollinated before the stigma was removed