Problem 142 - Objective Biology for NEET

Question

Which of the following helps in the transportation of minerals? (a) Xylem (b) Phloem (c) Both (a) and (b) (d) None of these

Step-by-Step Solution

Answer

The correct answer is (a) Xylem.

Step 1 Understand plants anatomy

Firstly, we need to understand the parts of the plant mentioned in the exercise. The Xylem and the Phloem are both tissues found within the stem of a plant. They both play crucial roles in the transportation of substances throughout the plant.

Step 2 Identify functions of Xylem and Phloem

Next, let's identify what each tissue does: \n\n- The Xylem primarily transports water and nutrients absorbed from the soil by the roots to the rest of the plant. \n\n- The Phloem primarily transports sugar and other metabolic products from the leaves, where they are synthesized, to other parts of the plant.

Step 3 Determine which tissue transports minerals

Finally, let's determine which tissue helps in the transportation of minerals. From the functions identified in step 2, it is clear that it is the Xylem that is involved in the transportation of water and dissolved minerals from the roots to the rest of the plant.

Key Concepts

Xylem

In plants, xylem is a specialized tissue responsible for transporting water and minerals from the roots to different parts of the plant. This process is essential for plant growth and survival. Xylem vessels form long tubes that stretch from the roots to the leaves. These tubes are created from dead cells, which form a continuous pipeline for efficient water transport.

• Transpiration Pull: Water is pulled upwards from the roots to the leaves through the process called transpiration.
• Cohesion and Adhesion: Water molecules stick together and to the walls of the xylem tubes, helping in their upward movement.
• Role in Mineral Transport: Xylem not only carries water but also dissolves minerals absorbed from the soil.

The xylem ensures that essential nutrients reach all parts of the plant, enabling processes like photosynthesis and growth.

Phloem

Phloem is another crucial tissue in plants, responsible for transporting organic nutrients, particularly sugars, from the site of production to other parts of the plant. This process is known as translocation, and it mainly occurs from the leaves to the stems and roots.

• Sugar Source and Sink: Leaves serve as the sugar source, while other plant parts like roots and fruits act as sinks where sugars are needed.
• Living Cells: Unlike xylem, phloem is made up of living cells, which assist in the active transport of substances.
• Bidirectional Flow: Phloem transports substances in various directions, ensuring distribution to where they are needed.

Phloem plays a vital role in energy distribution, supporting growth, reproduction, and storage within the plant.

Mineral Transport

Mineral transport in plants primarily occurs through the xylem. Plants absorb minerals from the soil through their roots. These minerals, essential for various plant functions, dissolve in water and are transported along with it throughout the plant.

• Absorption by Roots: Roots actively uptake minerals like nitrogen, potassium, and phosphorus from the soil.
• Role in Plant Metabolism: Minerals aid in synthesizing cell structures, chlorophyll, and proteins.
• Transport Mechanism: Dissolved minerals are carried upwards through the xylem vessels.

Effective mineral transport ensures the plant's health and its ability to perform critical biological processes.

Plant Anatomy

The anatomy of plants is intricately designed to support various functions that are essential for their survival. Two major tissues, the xylem and phloem, are fundamental to the plant's transport system. Each tissue has a distinct role in maintaining the plant system.

• Xylem: Transports water and minerals, offering structural support.
• Phloem: Transports sugars and organic nutrients.
• Interconnectivity: Both xylem and phloem run parallel within the plant's vascular bundles.
• Specialized Cells: Certain cells within these tissues are uniquely adapted for their respective functions.

Understanding plant anatomy allows us to appreciate how these vital transport systems are organized and how they contribute to overall plant health and functionality.