Bio 111 Photosynthesis & Cellular Respiration Vocabulary

Photosynthesis (Sections 5.1-5.3)

• Organisms that use photosynthesis: Plants, algae, and cyanobacteria.

• Autotrophs vs. Heterotrophs:

  • Autotrophs: Organisms that produce their own food using light energy (e.g., plants).

  • Heterotrophs: Organisms that obtain energy by consuming other organisms (e.g., herbivores and carnivores).

• Photosynthesis Definition: The process by which plants use light energy to produce glucose and oxygen.

• Balanced Chemical Equation for Photosynthesis:
  6CO2 + 6H2O + light energy → C6H12O6 + 6O2

• Reactant Molecules Entry and Atom Fate:

  • Carbon Dioxide (CO_2): Enters through stomata (small pores) on leaves and diffuses into chloroplasts within mesophyll cells.

  • Water (H_2O): Enters through the roots.

  • Carbon atoms from carbon dioxide end up in Glucose (C6H{12}O_6).

• Photosynthesis: Endergonic or Exergonic? Endergonic because it requires energy from sunlight to build complex molecules from simpler ones.

• Photosynthesis: Anabolic or Catabolic? Anabolic because it uses energy to build complex molecules (glucose).

• Oxidation in Photosynthesis:

  • Water (H_2O) is oxidized.

  • It becomes Oxygen (O_2) after oxidation during the light reactions.

• Reduction in Photosynthesis:

  • Carbon Dioxide (CO_2) is reduced.

  • It becomes Glucose (C6H12O6) after reduction during the Calvin cycle.

• Pigment Molecule Definition: A molecule that reflects color and uses light energy to drive photosynthetic reactions.

• Primary Photosynthetic Pigment: Chlorophyll a.

• Light Absorption by Primary Pigment: Violet-blue and red light are absorbed best by chlorophyll a.

• Why Leaves Are Green: Green light isn't absorbed well, so it is reflected, making leaves appear green.

• Chloroplast Anatomy:

  • Double membrane structure.

  • Thylakoids are internal membrane sacs containing chlorophyll; stacks of thylakoids are called grana.

  • Stroma is the fluid-filled space around the thylakoids.

• Light Reactions vs. Carbon Reactions:

  • Light Reactions:

    • Location: Thylakoid membrane.

    • Requirements: Light is required.

    • Process: Water (H_2O) is split, releasing oxygen; light energy excites electrons.

    • Intermediate Electron Carrier: NADP+ accepts electrons and hydrogen ions to become NADPH.

    • Energy Source: Light.

    • Water Splitting: Occurs during light reactions, producing O_2, H^+, and electrons.

  • Carbon Reactions (Calvin Cycle):

    • Location: Stroma of the chloroplast.

    • Requirements: ATP and NADPH, which are produced during light reactions.

    • Process: Carbon dioxide (CO_2) is converted into glucose.

    • Glucose Formation: Occurs during carbon reactions of photosynthesis.

    • Carbon Source: Carbon came from CO_2.

    • Hydrogen Source: Hydrogen from H_2O.

    • Energy Source: Energy for glucose formation is provided by ATP and NADPH.

• Source of Oxygen Gas on the Planet: The oceans algae and photosynthesis.

Intro to Cellular Respiration (Section 6.1)

• ATP Synthesis

  • Chemical Components of ATP: Adenine base, ribose sugar, and three phosphate groups.

  • Storing Energy by Phosphorylating ADP to ATP:

    • Energy is stored in the phosphate bonds of ATP.

    • Phosphorylation changes the shape of the enzyme, allowing it to function and work.

  • Importance of ATP for Life: ATP drives almost all embryonic reactions

• Aerobic Cellular Respiration

  • Definition: A process in the mitochondria that uses oxygen to break down glucose, producing carbon dioxide, water, and ATP.

  • Balanced Chemical Equation for Aerobic Cellular Respiration: C6H{12}O6 + 6O2 \rightarrow 6CO2 + 6H2O

    • (1) Reactant Entry:

      • Glucose enters from eating food.

      • Oxygen enters through inhalation (breathing).

    • (2) Atom Fate:

      • Carbon atoms from glucose end up as CO_2.

      • Hydrogen from glucose and oxygen end up in H_2O.

    • (3) Product Exit:

      • Carbon dioxide exits through breathing (exhaling).

      • Water exits through sweat.

    • (4) Oxidation:

      • Glucose is oxidized.

      • It becomes CO_2 after oxidation.

    • (5) Reduction:

      • O_2 is reduced.

      • It becomes H_2O.

  • Cellular Respiration: Catabolic or Anabolic? Catabolic because it breaks down complex molecules into simpler ones.

  • Cellular Respiration: Endergonic or Exergonic? Exergonic because it releases energy stored in bonds to produce ATP.

  • Reverse Reaction Name: Photosynthesis

• ATP Phosphorylation Equation:
  ADP + P_i \rightarrow ATP

  • ATP Phosphorylation: Endergonic or Exergonic? Endergonic because it requires an input of energy to form the high-energy phosphate bond in ATP.

  • ATP Phosphorylation: Anabolic or Catabolic? Anabolic because smaller molecules build complex molecules (add phosphate and build ATP).

Anatomy of Mitochondria (Section 6.3)

• Function of Mitochondria: Energy production.

• Cytosol Location: Surrounds the mitochondria.

• Mitochondrial Structures:

  • Outer Membrane: Smooth.

  • Inner Membrane: Folded to increase surface area.

  • Intermembrane Compartment: Space between the inner and outer membranes.

  • Matrix: Liquid portion of the cell; innermost portions occur here.