Photosynthesis and Respiration
Key equations, organelles, anaerobic pathways, limiting factors, and experiments for photosynthesis and respiration.
Keyboard Shortcuts
💡 Pro tip: Use keyboard shortcuts for faster studying!
Study Smart Tips for Photosynthesis and Respiration
Master these concepts using proven study techniques that actually work:
Active Recall
Test yourself before flipping each card to strengthen memory retention
Spaced Repetition
Review difficult cards more frequently than easy ones
Multiple Sessions
Break study time into shorter, focused sessions
Explain Aloud
Verbalize answers to reinforce understanding
Questions Covered in This Set
12 cards to master
Write the word equation for photosynthesis.
Carbon dioxide + water → glucose + oxygen (light and chlorophyll needed). Balanced: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Write the balanced equation for aerobic respiration.
C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy (ATP)
Which organelles carry out photosynthesis and respiration?
Photosynthesis: chloroplasts (plant/algal cells). Respiration: mitochondria (all living cells).
Is photosynthesis endothermic or exothermic? What about respiration?
Photosynthesis is endothermic (absorbs light energy); respiration is exothermic (releases energy as ATP).
Common exam trap: do plants only respire at night?
No — plants respire 24 hours a day. In good light they photosynthesise faster than they respire, giving a net release of oxygen.
Anaerobic respiration in animal muscle
Glucose → lactic acid + energy. Lactic acid causes fatigue and creates an oxygen debt, repaid by extra breathing afterwards.
Anaerobic respiration in yeast (fermentation)
Glucose → ethanol + carbon dioxide + energy. Used in brewing (ethanol) and bread-making (CO₂ makes dough rise).
Name the three main limiting factors of photosynthesis.
Light intensity, carbon dioxide concentration, and temperature (chlorophyll amount is sometimes counted as a fourth).
How do you read a limiting factor graph?
Steep rising part = that factor is limiting; flat plateau = another factor is limiting. Temperature graphs peak then crash as enzymes denature above ~40 °C.
How do you test a leaf for starch?
Boil in water (kill tissue), boil in ethanol (remove chlorophyll), rinse, add iodine. Blue-black = starch present = photosynthesis occurred.
Describe the pondweed (Elodea) bubble experiment controls.
Count O₂ bubbles at different lamp distances; use sodium hydrogen carbonate solution for plenty of CO₂ and a water beaker to absorb heat so temperature stays constant.
How can you show that seeds are respiring?
Bubble the gas through limewater — it turns milky, showing CO₂ is released. Boiled (dead) seeds act as the control.
