Which micronutrient is essential for plant growth in small quantities and is often represented by the symbol 'Fe'?

The essential micronutrient represented by the symbol 'Fe' is iron. Iron plays a crucial role in plant growth, primarily because it is a vital component of chlorophyll, the molecule responsible for photosynthesis. This process allows plants to convert sunlight into energy, which is essential for their growth and development.

In addition to its role in chlorophyll synthesis, iron is involved in various enzymatic functions and activities that affect nitrogen metabolism and respiration, both critical for overall plant health. While plants require iron in minute quantities, a deficiency can lead to chlorosis, characterized by yellowing of leaves due to impaired chlorophyll production.

Manganese, copper, and molybdenum are also important micronutrients, but they are represented by different symbols and play distinctive roles in plant physiology. Manganese (Mn) is involved in photosynthesis and enzyme activation, copper (Cu) is crucial for photosynthesis and overall plant metabolism, and molybdenum (Mo) is vital for nitrogen fixation and nitrate reduction. Each of these nutrients has specific functions, but iron's unique role in chlorophyll production and energy conversion makes it critical for plant growth.