Photosynthesis and Cellular Respiration: A Cheat Sheet

Photosynthesis converts light energy into chemical energy stored in glucose, while cellular respiration releases this stored energy to produce ATP. These processes are complementary, forming a vital cycle for life on Earth.

Core Principles

Photosynthesis uses solar energy, water, and carbon dioxide to create glucose and oxygen within chloroplasts.
Cellular respiration uses glucose and oxygen to produce ATP, carbon dioxide, and water within mitochondria.
Energy flows from the sun, is captured by photosynthesis, and then released by cellular respiration, ultimately dissipating as heat.
Enzymes are crucial biological catalysts that speed up reactions by lowering activation energy, fitting substrates at their active sites.

Action Steps

Identify reactants (CO2, H2O, solar energy) and products (glucose, O2) of photosynthesis.
Identify reactants (glucose, O2) and products (CO2, H2O, ATP) of cellular respiration.
Recognize that enzymes lower activation energy (Ea) to facilitate reactions.
Understand that ATP is the energy currency, generated from ADP + P.
Distinguish between light-dependent (light reactions) and light-independent (Calvin cycle) stages of photosynthesis.

Formulas

Photosynthesis: $energy + 6 CO_2 + 6 H_2O \xrightarrow{solar\ energy, pigments} C_6H_{12}O_6 + 6 O_2$
Cellular Respiration: $C_6H_{12}O_6 + 6 O_2 \rightarrow 6 CO_2 + 6 H_2O + energy (ATP)$
Free Energy Change: $\Delta G = G_{products} - G_{reactants}$

Key Terms

Photosynthesis: The process by which plants, algae, and cyanobacteria use solar energy to convert carbon dioxide and water into glucose and oxygen.
Cellular Respiration: The process by which cells break down glucose in the presence of oxygen to release energy in the form of ATP.
Chloroplast: The organelle in plant cells where photosynthesis takes place.
Mitochondrion: The organelle in eukaryotic cells where cellular respiration takes place.
ATP (Adenosine Triphosphate): The primary energy currency of cells, used to power cellular activities.
Enzyme: A biological catalyst that speeds up chemical reactions without being consumed.
Activation Energy (Ea): The minimum energy required to initiate a chemical reaction.
Light Reactions: The first stage of photosynthesis, which captures solar energy and produces ATP and NADPH.
Calvin Cycle: The second stage of photosynthesis, which uses ATP and NADPH to convert carbon dioxide into glucose.
Glycolysis: The initial breakdown of glucose into pyruvate, occurring in the cytoplasm.
Chemiosmosis: The process of ATP production linked to an electrochemical gradient, particularly the flow of H+ ions.
Oxidation: The loss of electrons in a chemical reaction (OIL).
Reduction: The gain of electrons in a chemical reaction (RIG).