8.1 Overview of Photosynthesis

8.1 Overview of Photosynthesis

  • By the end of this section, you will be able to explain the importance of photosynthesis to other living organisms.
    • The only biological process that can capture energy from the sun and convert it into chemical compounds is it.
    • Oxygen is needed for many living organisms.
    • The electrons' energy is captured by the sun and stored in the bonds of sugar.
  • During the Carboniferous Period, 350 to 200 million years ago, sunlight energy was captured and stored by photosynthesis, which is what the energy from the burning of coal and petroleum products is today.
  • Plants, algae, and a group ofbacteria called cyanobacteria are the only organisms capable of performing photosynthesis.
    • A third group ofbacteria synthesise sugars, not by using sunlight's energy, but by taking energy from chemical compounds.
  • Plants, algae, and cyanobacteria use sunlight as an energy source to synthesise their organic compounds.
    • At times planktonic algae can grow completely on the surface of the water.
    • In a deep sea vent, thermophilicbacteria capture energy from other compounds to produce organic compounds.
    • There are a variety of animals surrounding the vents that derive their energy from the bacteria.
  • The importance of photosynthesis is more than that it can capture sunlight's energy.
    • A lizard can use the sun's energy to warm up in a process called behavioral thermoregulation.
  • Heterotrophs use those carbohydrates to power their synthesis.
    • When a top predator, such as a wolf, preys on a deer, the wolf is at the end of an energy path that went from nuclear reactions on the surface of the sun, to visible light, to photosynthesis, to vegetation, to deer, and finally to the wolf.
  • The food chain has energy stored in it.
    • The predator that eats these deer gets some of the energy that came from the deer.
    • The process of photosynthesis requires specific wavelength of visible sunlight, carbon dioxide, and water.
    • After the process is complete, it releases oxygen and produces glyceraldehyde-3-phosphate (G3P), as well as simple carbohydrate molecule (high in energy) that can be converted into sugar.
    • All living things need energy and carbon to survive.
  • Photosynthesis uses solar energy, carbon dioxide, and water.
    • Oxygen is a waste product.
  • The basic equation is easy to understand.
    • The process takes place in many steps.
    • The primary energy source in cells is made from two three-carbon G3Ps.
  • It is important to become familiar with the structures involved before learning the details of how photoautotrophs turn sunlight into food.
  • Plants usually take place in leaves with several layers of cells.
    • The underside of the leaf is where the stomata are located, which helps to minimize water loss due to high temperatures on the upper surface of the leaf.
    • The guard cells that regulate the opening and closing of the stomata are flanked by each stoma.
  • Most of the cells in the mesophyll are chlorogenic.
    • Chloroplasts are derived from ancient free-living cyanobacteria and have a double envelope.
  • Chlorops have an outer and an inner shell.
    • A third layer is formed by stacks of thylakoids called grana.
  • On a hot, dry day, guard cells of plants close their stomata to conserve water.
  • The first two stages of photosynthesis are light dependent and light independent.
    • Light-independent reactions do not use light as a reactant, but they need the products of light- dependent reactions to function.
    • Several of the light-independent reactions are activated by light.
    • These are referred to as energy carriers and are used to temporarily store the energy.
    • The energy carriers that move energy from light-dependent reactions to light-independent reactions are rich in energy and can be thought of as full.
    • The "empty" energy carriers return to the light-dependent reaction to get more energy after the energy is released.
  • The Calvin cycle is one of the two stages of photosynthesis.
    • Light energy can be used in light- dependent reactions to make a substance.
    • The Calvin cycle uses energy from these compounds to make G3P from CO2.
  • There is a link to learn more about photosynthesis.