Question

Assertion: Ethylene helps the plants to increase their surface area for absorption. Reason: Ethylene promotes root growth and root hair formation.

Short answer

Indeed, Ethylene contributes to increasing a plant's surface area for absorption. It does this by promoting root growth and root hair formation, which enlarge the plant's surface area over which water and nutrients could be absorbed from the soil.

Step-by-step solution

Understanding the role of Ethylene

Ethylene is a gaseous plant hormone that affects plant growth and development. It plays a crucial role in various aspects of the plant life cycle, including seed germination, cell division, fruit ripening, senescence, and stress responses.

Ethylene's effect on root growth and root hair formation

Among many roles, Ethylene stimulates the elongation of the cells resulting in root elongation. It also promotes the formation of root hairs. Root hairs are small, thin extensions resulting from rapid cell elongation and they play a crucial role in water and nutrient uptake.

Connecting increased surface area for absorption to Ethylene

When Ethylene promotes root growth and root hair formation, it effectively increases the contact points with the soil and as a result, enlarges the surface area over which the plant can absorb water and nutrients. Root hair extensions can enter smaller soil pores accessing more resources, hence enhancing absorption.

Key concepts

Plant Hormones

In the world of plants, hormones are crucial chemical messengers. They coordinate various activities such as growth, development, and responses to the environment. Unlike animal hormones, which are often specific to particular glands, plant hormones can act in diverse parts of the plant.
One of these important plant hormones is ethylene, which is unique in being a gas. Ethylene affects processes ranging from fruit ripening to leaf shedding. It helps plants respond to stresses like flooding or injuries. This hormone, though lesser-known, plays a significant role in ensuring that plants adapt to their surroundings efficiently.

• Coordinate growth and developmental processes
• Assist in stress response
• Include ethylene as a key hormone for adaptability

Ethylene is especially significant due to its ability to shape plant behavior in response to changes in the environment, allowing for a restructured growth path where needed.

Root Growth

Root growth in plants is a fundamental process involving the elongation and creation of new root cells. This ensures the plant can anchor itself and effectively access water and nutrients from the soil.
Ethylene plays a pivotal role in promoting root growth by stimulating cell elongation. This elongation increases the reach of the roots into deeper or wider soil zones.
Moreover, ethylene can alter the direction of growth, helping the root navigate around obstacles.
Roots are not just stability providers; they are active metabolic zones that link the plant to its nourishment sources.

• Vital for plant stabilization
• Ethylene enhances root cell elongation
• Aims at maximizing soil resource access

The extension of roots not only helps the plant secure itself but also prepares the plant to better cope with challenging soil conditions.

Root Hair Formation

Root hair formation is a specialized growth process that involves the development of tiny hair-like structures on the root surface. These root hairs play a crucial role in the plant's ability to absorb water and nutrients.
Ethylene effectively triggers the formation of root hairs, enhancing their density and length. This results in a more extensive network for absorption.
Each root hair acts as a mini channel, penetrating deeper into the soil matrix and reaching nutrients that might otherwise be inaccessible.

• Enhances nutrient and water absorption
• Ethylene boosts formation and effectiveness of root hairs
• Increases absorption interface between plant and soil

In essence, root hairs multiply the plant’s ability to uptake resources, reinforcing its growth and survival capability, especially in nutrient-poor soils.

Surface Area for Absorption

Surface area for absorption in plants refers to the total exposed area of the roots and root hairs that can interact with the soil. The larger this area, the higher the potential uptake of water and minerals.
Ethylene is vital as it drives both root elongation and root hair formation, consequently expanding the surface area. This increase allows plants to capture more resources crucial for their growth and sustenance.
When root hairs extend into tiny soil pore spaces, it creates additional access points, maximizing resource extraction from varied soil environments.

• Affected positively by ethylene-driven changes
• Leads to enriched water and mineral absorption
• Supports overall plant vitality and productivity

This increased surface area, especially in challenging environments, means a stronger, more resilient plant adapting to its ecological niche.