A mineral deficiency is likely to affect older leaves more than younger leaves if
a. The mineral is a micronutrient
b. The mineral is very mobile within the plant
c. The mineral is required for chlorophyll synthesis
d. The mineral is a macronutrient

Verified step by step guidance

1. Understand the concept of mineral mobility in plants: Minerals that are mobile can be transported from older leaves to younger leaves when there is a deficiency.
2. Identify the characteristics of mobile minerals: Mobile minerals are typically those that can be relocated within the plant to support new growth, often affecting older leaves first.
3. Consider the role of older leaves: Older leaves may show deficiency symptoms first if the plant reallocates mobile minerals to younger, growing tissues.
4. Analyze the options: Determine which option describes a scenario where older leaves are affected due to mineral mobility.
5. Conclude based on mobility: The correct answer will be the one that indicates the mineral is mobile, as this would lead to older leaves showing deficiency symptoms first.

Key Concepts

Mineral Mobility in Plants

Mineral mobility refers to the ability of a mineral to move from older to younger tissues within a plant. Mobile minerals, such as nitrogen, phosphorus, and potassium, can be relocated to new growth areas when there is a deficiency, often affecting older leaves first. Understanding mineral mobility helps explain why older leaves show deficiency symptoms before younger ones.

Role of Minerals in Chlorophyll Synthesis

Chlorophyll synthesis is crucial for photosynthesis, and certain minerals like magnesium and iron are essential for this process. A deficiency in these minerals can lead to chlorosis, where leaves turn yellow due to insufficient chlorophyll. If a mineral required for chlorophyll synthesis is deficient, it can significantly impact plant health and growth.

Macronutrients vs. Micronutrients

Macronutrients are nutrients required by plants in larger quantities, such as nitrogen, phosphorus, and potassium, while micronutrients are needed in smaller amounts, like iron, manganese, and zinc. Both types are vital for plant growth, but their required quantities and roles differ. Understanding the distinction helps in diagnosing and addressing nutrient deficiencies in plants.