Advanced Science Primary 6 Energy

A plant was placed in a sealed jar with a supply of water but no light for three days. What would happen to the level of oxygen and carbon dioxide in the jar?

A Both remain the same
B Oxygen decreases, Carbon Dioxide increases
C Oxygen increases, Carbon Dioxide decreases
D Both increase
Show Worked Solution

Worked Solution

Step 1: Without light, the plant cannot perform photosynthesis to produce oxygen. Step 2: However, the plant is a living thing and must perform respiration 24/7. Step 3: Respiration uses up oxygen and releases carbon dioxide. Therefore, oxygen levels drop and carbon dioxide levels rise.

Correct answer: Oxygen decreases, Carbon Dioxide increases

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