Sunlight Savvy
What is the primary source of energy for photosynthesis?
Sunlight
What gas do plants take in for photosynthesis?
Carbon dioxide (CO₂)
What sugar is produced during photosynthesis?
Glucose
Where in the chloroplast does the light-dependent reaction occur?
Thylakoid membranes
Name one factor that can limit photosynthesis.
Light intensity, temperature, or CO₂ concentration
What pigment absorbs light in plants?
Chlorophyll
What molecule do plants need along with CO₂ to make glucose?
Water (H₂O)
What gas is released as a byproduct of photosynthesis?
Oxygen (O₂)
Where does the Calvin cycle take place?
Stroma
What happens to photosynthesis at very low temperatures?
The rate decreases because enzymes work slower.
Explain why chlorophyll appears green.
It reflects green light and absorbs red and blue light.
Explain the role of water in photosynthesis.
Water is split to provide electrons and hydrogen ions, releasing oxygen.
Compare glucose and oxygen in terms of their use by other organisms.
Glucose stores energy; oxygen is needed for cellular respiration.
Explain the role of ATP and NADPH in the Calvin cycle.
They provide energy and electrons to convert CO₂ into glucose.
Explain how water shortage affects photosynthesis.
Plants close stomata, reducing CO₂ intake and slowing photosynthesis.
How does light intensity affect the rate of photosynthesis?
Increasing light generally increases the rate until a maximum is reached.
Predict what would happen if CO₂ levels in the atmosphere doubled.
Photosynthesis rates could increase, assuming other factors are not limiting.
How is the glucose made during photosynthesis used by the plant?
For energy (ATP), building cell structures, or storing as starch.
Compare the purpose of light-dependent reactions vs. the Calvin cycle.
Light-dependent reactions capture energy; Calvin cycle uses that energy to make sugars.
Predict how photosynthesis rates would change if plants were exposed to red vs. green light.
Red light increases photosynthesis; green light is less effective.
Construct an explanation for why plants in shade have more chlorophyll than those in direct sunlight.
Plants adapt to capture more light by producing more chlorophyll in low-light conditions.
Construct an explanation for how photosynthesis balances carbon in the ecosystem.
Plants convert CO₂ into glucose, reducing atmospheric CO₂ and providing energy for the food web.
Explain how photosynthesis and cellular respiration form a cycle of energy in ecosystems.
Photosynthesis stores energy in glucose; cellular respiration releases energy, which plants and animals use.
Construct an explanation for why photosynthesis slows if the thylakoid membranes are damaged.
Light-dependent reactions can’t occur efficiently, reducing ATP/NADPH production and glucose synthesis.
Construct an explanation for how climate change could impact photosynthesis in global ecosystems.
Changes in temperature, CO₂ levels, and water availability can alter rates, affecting energy flow and carbon balance.