Problem 114 - Objective Biology for NEET

Question

Assertion: Boron is required for the uptake and utilization of calcium ion. Reason: Boron is not required for carbohydrate translocation.

Step-by-Step Solution

Answer

The assertion is correct, but the reason is incorrect and does not provide a logical explanation to the assertion.

Step 1: Analyse Assertion

Boron is a trace nutrient that influences the uptake and utilization of other minerals, particularly calcium. Therefore, the assertion 'Boron is required for the uptake and utilization of calcium ion' is correct.

Step 2: Analyse Reason statement

'Boron is not required for carbohydrate translocation' is a statement that needs to be assessed. However, Boron does play a role in supporting the movement (translocation) of carbohydrates in plants. So, the provided reason is incorrect.

Step 3: Compare Assertion and Reason

The assertion is correct, but the reason is incorrect. Moreover, even if the reason were correct, it does not provide a logical explanation or support for the assertion.

Key Concepts

Boron Function

Boron is an essential micronutrient that plays a crucial role in plant growth and development. Although plants need it in tiny amounts, it significantly impacts several functions within the plant system. One of the key roles of boron is assisting with the uptake and utilization of calcium, another vital nutrient. Calcium is integral for cell wall structure and stability. Boron helps transport and anchor calcium into structural components of the cell wall.
This action strengthens the plant's physical structure, enhancing its ability to resist diseases and pests. Without adequate boron, calcium cannot be effectively used within the plant, leading to problems like poor growth and development.
Boron also contributes to:

• Cell wall synthesis
• Cell division and elongation
• Hormone regulation and balance

Understanding boron's multi-faceted role helps highlight its importance in holistic plant health management.

Calcium Uptake

Calcium is a secondary nutrient but is vital for plant health. It is vital for maintaining the structural integrity of plants. Though it is abundant in soil, its uptake by plants needs to be facilitated efficiently. This is where boron plays a supportive role. Boron helps transport calcium to plant cells where it forms a critical part of cell walls and membranes.
Calcium is essentially "glue" in the plant's architecture, giving rigidity to the cell structure. Its absence can cause issues such as weak stems, poor root development, and vulnerable tissue in plants.
Moreover:

• Calcium affects enzyme activity and influences cell division and growth.
• It is crucial for the integrity and permeability of cell membranes.
• Adequate calcium prevents some physiological disorders, such as blossom end rot.

This nutrient's proper uptake hinges largely on boron's presence, showcasing their interconnected roles in plant nutrition.

Carbohydrate Translocation

Carbohydrate translocation is the process of transporting sugars and other organic compounds from the site of production (usually leaves) to other parts of the plant. These carbohydrates are vital for energy and growth in non-photosynthetic parts like roots and fruits. Contrary to misconceptions, boron is necessary for effective carbohydrate translocation. It supports the movement of sugars through plant tissues.
This element ensures that carbohydrates reach the parts of the plants where they are most needed for growth and storage. Without boron, this movement could be hindered, leading to reduced growth and energy supply where it's needed most.
Key roles of boron in this process include:

• Stabilizing sugar transport by enhancing cell membrane stability.
• Facilitating sugar-bonding through pectin in the cell walls.
• Supporting energy allocation for reproductive growth and seed development.

Such roles make boron indispensable in the lifecycle of plants and reinforce its necessity beyond just supporting calcium uptake.