Class 10 Biology Chapter 3
Absorption by Roots-The Processes Involved Important Questions

Here, you'll find important questions related to Chapter 3 : Absorption by Roots- The Processes Involved for ICSE Class 10 Biology. These questions have been crafted to assist students in their preparation for the ICSE Class 10 Biology Examination in 2023–24. By practising various question types, students can clarify their doubts, enhance their exam readiness, boost their confidence, and refine their problem-solving skills.

Introduction

In the third chapter of ICSE Class 10 Biology, we embark on a fascinating journey into the intricate world of "Absorption by Roots - The Processes Involved." This chapter delves into the fundamental processes by which roots of plants absorb water and nutrients from the soil, a crucial aspect of a plant's survival and growth. To master this subject, students not only need a solid understanding of the concepts but also comprehensive practice with biology questions for Class 10 ICSE.
In this chapter, we will unravel the mysteries behind root absorption mechanisms, exploring how plants utilise various structures and processes to uptake essential substances. Additionally, we will delve into the intricacies of osmosis, diffusion, and active transport—concepts that are vital to comprehending the intricate world of plant physiology. As you navigate through this chapter, you'll find valuable insights and a thorough exploration of important questions for Class 10 biology ICSE, enabling you to strengthen your knowledge and prepare effectively for your examinations. So, let's delve into the absorbing world of root processes and equip ourselves with the essential tools to understand the life of plants at a cellular level.

What is Absorption by Roots- The Processes Involved  ?

Absorption by Roots - The Processes Involved refers to the mechanisms and physiological processes through which plant roots uptake water, minerals, and nutrients from the soil. This vital function is essential for a plant's growth, development, and overall survival. Several key processes are involved in root absorption:

• Osmosis: Osmosis is the passive movement of water molecules from an area of higher water concentration (usually in the soil) to an area of lower water concentration (within the root cells). This process occurs through the semipermeable cell membranes of root cells.
• Diffusion: Diffusion is the movement of dissolved nutrients and ions from areas of higher concentration in the soil to areas of lower concentration within the root cells. It is also a passive process driven by concentration gradients.
• Active Transport: In cases where nutrients are present in lower concentrations in the soil, plants utilise active transport mechanisms to move these essential substances against their concentration gradients into the root cells. This process requires energy, typically derived from ATP (adenosine triphosphate).
• Root Hairs: Root hairs are tiny, finger-like extensions that increase the surface area of the root system. They play a crucial role in enhancing water and nutrient absorption as they come into close contact with soil particles.
• Mycorrhizal Associations: Many plants form symbiotic relationships with mycorrhizal fungi, which extend the root's reach and increase its ability to absorb water and nutrients from the soil.
• Root Pressure and Transpiration: The movement of water and nutrients from roots to the rest of the plant is facilitated by root pressure and transpiration. Root pressure helps push water and nutrients into the xylem vessels, and transpiration (water loss through leaves) creates a negative pressure that draws water and nutrients upward through the plant.

Understanding these processes is essential for students studying ICSE Class 10 Biology, as they provide insights into how plants efficiently extract essential resources from their environment. Moreover, practising important questions for Class 10 ICSE biology related to root absorption processes can help reinforce and apply this knowledge effectively.

Class 10 Biology Absorption by Roots- The Processes Involved Important Questions and Answers

Q1. Process of endosmosis stops :

Options

(a) When the water concentrations are unequal
(b) When the solutions become isotonic
(c) When the leaves fall
(d) When there is no light

Ans. (b)  

Explanation:
The movement of water molecules inside the cell stops when the solution becomes isotonic with respect to the surrounding solution. Isotonic refers to an equal concentration of both solute and solvent.

Q2. Which structures must be present in a cell for osmosis to take place?

Options

(a) Cell (sap) vacuole and cell wall
(b) Cell wall and cell membrane
(c) Chloroplast and cytoplasm
(d) Cytoplasm and cell membrane

Ans. (d) Cytoplasm and cell membrane
Explanation:
In order to function, cells are required to move materials in and out of their cytoplasm via their cell membranes. Therefore cytoplasm and cell membrane is an important requirement.

Q3. Give the reason for the given statement:
Drops of water on a leaf of a plant like peepal does not enter the leaf by osmosis.

Explanation:
Drops of water on a leaf of a plant like peepal does not enter the leaf by osmosis due to the presence of cuticle, which does not allow water molecules to pass through it.

Q4. What is the water potential ?

Explanation:
Water potential is a measure of potential energy of water per unit volume or the difference in potential energy between a given water sample and pure water.

Q5. Differentiate between Active transport and Passive transport.

Explanation:‍

ICSE Class 10 Biology Chapter wise Important Questions

Conclusion

The understanding of absorption by roots and the processes involved is vital in comprehending how plants acquire essential nutrients and water from the soil..For students aspiring to excel in this aspect of biology and reinforce their knowledge, exploring additional ICSE Class 10 biology questions related to absorption by roots is highly recommended. If you seek additional practice and wish to enhance your understanding of the chapter's content, Oswal.io provides a comprehensive collection of questions to facilitate your learning process.

Frequently Asked Questions

Q1 : What is transpiration pull? How is it caused?

Ans: As the water is lost from the leaf surface by transpiration, more water molecules are pulled up due to the tendency of water molecules to remain joined (cohesion), and thus to produce a continuous column of water through the stem is called transpiration pull. Transpiration pull is an important force which causes the ascent of sap. Negative pressure or tension is produced in the xylem that pulls the water from the roots and soil.

Q2 : Leaves of the sensitive plant wilt and droop down on a slight touch. What mechanism brings about this change?

Ans:  The rapid drooping of the leaves of the sensitive plant (Mimosa pudica) is an outstanding example of turgor movement. If one of the leaves is touched, even lightly, the leaflets fold up and within 2 to 3 seconds, the entire leaf droops. If the leaf is touched somewhat strongly, the wave of folding and drooping spreads from the stimulated leaf to all neighbouring leaves. Slowly, the leaves recover and again stand erect. In this plant, the stimulus of touch leads to loss of turgor at the base of petioles called a pulvinus.

Q3 : Explain how soaked seeds swell up and burst their seed coats.

Ans: Imbibition is the passive absorption of water by substances such as cellulose (in the cell wall) and starch. Turgor is the pressure set up inside the plant cells due to hydrostatic pressure on the cell walls on account of incoming water as a result of endosmosis. The seeds swell up when soaked in water due to imbibition and endosmosis. The force generated by the water thus absorbed is strong enough to make the seed coats burst. Hence, soaked seeds when kept in a fully filled closed container burst it open with pressure.

Q4 : Concentration of mineral nutrient elements is higher inside the root-hairs than in the surrounding soil. How do roots take them in from the soil?

Ans:  The concentration of mineral nutrient elements is higher inside the root-hairs than in the surrounding soil because the absorption of mineral elements from the soil involves active transport by the cells. Minerals may also be absorbed as ions rather than as salts. The dilute solution of water and mineral salts, absorbed from the soil by the roots, can be used for food manufacture in the leaves, only if it can travel up to the highest points of the plant. This upward flow occurs through the xylem.

Q5 : Give two examples of turgor movements in plants.

Ans: Mimosa pudica is an outstanding example of turgor movement. The rapid dropping of the leaves of the sensitive plants. If one of the leaves is touched, even lightly, the leaflets fold up and within 2 to 3 seconds, the entire leaf droops. If the leaf is touched somewhat strongly, the wave of folding and drooping spreads from the stimulated leaf to all neighbouring leaves.Similar turgor movements are found in insectivorous plants whose leaves close up to entrap a living prey. The bending movement of certain flowers towards the sun and the sleep movements of the leaves of certain plants at night are also due to turgor movements.