The leaves of the plants are given a light source for photosynthesis. State, in words or symbols, the equation for photosynthesis.
The roots of the plants are supplied with a nutrient solution. The nutrient solution contains magnesium ions. Air is forced through the nutrient solution using an air stone with many very small holes. Explain the advantage to the cells of the plant roots of forcing air through the nutrient solution using the air stone.
State the type of cell in plant roots that takes up magnesium ions from the solution.
State the process that moves magnesium ions against a concentration gradient into this type of cell.
Farmers grew groups of 20 tomato plants for the same duration in nutrient solutions with a range of magnesium ion concentrations. State the best magnesium ion concentration for growth.
Explain your answer by using the investigation results and your knowledge of why magnesium ions are important to plants.