Photosynthesis/Respiration

• Photosynthesis

  • process used by plants, algae and some bacteria to turn sunlight into energy
  • converts carbon dioxide (CO2) abd water into food (sugars) and oxygen
• Chlorophyll

  • chemical reaction that gives plants their green color
• 4 main steps of photosynthesis:

  1. Absorption of light
  2. Transfer or electron
  3. Production of ATP
  4. Carbon fixation
• Type of reactions:

  • Light-dependent Reactions
  • Light-independent Reactions
• Light-dependent reactions - when a poton of light hits the reaction center, a pigment molecule such as chlorophyll releases an electron
• Light-independent reaction (Calvin Cycle)

  • 3-step process that generates sugar for plant
  • (1) carbon fixation
  • (2) 3-PGA is reduced, produces two glyceraldehyde 3-phospate (G3P) molecules
  • (3) regenarating rubisco - plant produces glucose or sugar
• Main events:

  • Chlorophyll absorbs light energy
  • The light energy is converted into chemical energy when the water molecules are split into hydrogen and oxygen
  • Carbon dioxide is reduced to carbohydrates
• Purpose:

  • Plants are autotrops (produces their own food)
  • Without this process, life on Earth would not be possible
  • depend on plants for oxygen and food
• 2 Final products of photosynthesis:

  1. Glucose
  2. Oxygen
• What is the process of (cellular) respiration?

  • is the process by which organisms combine oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining activities and discarding, as waste products, carbon dioxide, and water.
• Why do plants need energy from respiration?

  • The plant requires cellular respiration in order to release the bound chemical energy in the glucose and make ATP for the use of metabolic activities of the cell.
  • Cellular respiration requires carbohydrates and oxygen. Hence, plants need to have the ability to find oxygen and carbohydrates.
• What is the main function of it in living things?

  • The primary function of respiration is to provide energy to the living things.
  • Living things obtain oxygen by respiration, which is used for the oxidation of food to release energy.
  • This energy is used by living things to perform all functions.
• What organelle is responsible for respiration in plants?

  • Mitochondria is the main organelle involved in the respiration.
  • Mitochondria are known as the powerhouses of the cell whose membranes are specialized for aerobic respiration.
  • The energy released is trapped in the form of ATP for use by all the energy-consuming activities of the cell.
• What is the 1st step of cellular respiration?

  • Glycolysis, the first step of cellular respiration, occurs in the cytoplasm of your cells.
  • During this process, a glucose molecule is broken down into two molecules of pyruvate (pyruvic acid).
  • This process requires the investment of 2 ATP molecules and yields 4 ATP in addition to the pyruvate and another type of molecule called NADH, which will contribute to the final step of cellular respiration.