How do plants utilize magnesium?

Plants utilize magnesium primarily to make chlorophyll, which is vital for the process of photosynthesis. Chlorophyll is the green pigment found in the chloroplasts of plant cells, and it plays a crucial role in absorbing light energy, particularly from the sun. This light energy is then used to convert carbon dioxide and water into glucose and oxygen during photosynthesis.

Magnesium is an essential component of the chlorophyll molecule, and without sufficient magnesium, plants cannot produce enough chlorophyll, leading to impaired photosynthesis. This can result in stunted growth and yellowing of leaves, a condition known as chlorosis.

The other options do not correctly describe the primary role of magnesium in plants. While plants do absorb sunlight through chlorophyll, they do not utilize magnesium for the absorption process itself. Storing energy is largely carried out through glucose and other carbohydrates, and building cell walls typically involves other elements and compounds, such as cellulose.