Word Equation
The two chemical substances needed for photosynthesis to happen
Carbon dioxide and water
Why is photosynthesis essential for plants?
Provides glucose (chemical energy/food)
Why can't plants just absorb food from the soil?
Photosynthesis needs to take place to make glucose
Light intensity, temperature, carbon dioxide concentration
How can we tell that pondweed is doing photosynthesis during the experiment?
It produces bubbles
The two products of photosynthesis
Why is photosynthesis important for humans?
Provides oxygen for respiration and glucose for food
How does water move from the roots to the leaves?
Through the stem
When light intensity is higher, does photosynthesis happen more quickly or more slowly?
More quickly
Which gas is released in the bubbles produced by the pondweed when it does photosynthesis?
Oxygen
The word equation for photosynthesis
Carbon dioxide + Water -> Glucose + Oxygen
How does photosynthesis help to reduce climate change?
Takes in carbon dioxide
What is the name for the part of a plant cell where photosynthesis happens?
Chloroplasts
Why does higher light intensity allow photosynthesis to happen more quickly?
More energy for the reaction to happen
Describe how you used a lamp, ruler and stopwatch to investigate how light intensity affected the rate of photosynthesis
The pondweed was placed at different distances from the lamp, and the number of bubbles produced in a set time was counted
Energy
What would happen to an ecosystem if photosynthesis suddenly stopped?
Plants would stop growing; animals would not have food to eat
What is the name for the molecule that plants use to store 'spare' glucose?
Starch
When the concentration of carbon dioxide increases, the rate of photosynthesis increases at first, then stops increasing. Why does this happen?
Another factor (light intensity or temperature) is limiting the rate of photosynthesis
A students says that counting bubbles is an unreliable way of measuring the rate of photosynthesis. How else could the rate of photosynthesis in pondweed by measured?
Collecting the oxygen produced and measuring the volume