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Maharashtra Board Class 12 Solutions for Biology Chapter 6 Plant Water Relation

Last updated date: 23rd May 2024
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Maharashtra Board Class 12 Solutions for Biology Chapter 6 Plant Water Relation – Download Free PDF with Solution

Class 12 Biology Chapter 6 teaches us about the different things plants need to survive. It also explains the relationship between plants and water retention. This chapter describes how water is retained by plants. The different processes of absorbing and retaining water by plants will be explained with examples in this chapter.

To understand these fundamental botanical concepts, refer to the Plant Water Relation solutions prepared by the experts. These solutions have been compiled in a simpler format to offer you a better platform for grabbing the concepts and learning how to answer fundamental questions easily.

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Access Maharashtra Board Solutions for Biology Class 12 Chapter 6 Plant Water Relation

Multiple Choice Questions

1. In soil, water available for absorption by root is ...................

  1. Gravitational water

  2. Capillary water

  3. Hygroscopic water

  4. Combined water

Ans: The correct answer is (b) Capillary water

A large amount of water is present in the soil. From soil with the help of roots plants absorb the water. The water goes through a fine capillary tube. So this water is known as capillary water.

2. The most widely accepted theory for the ascent of sap is ..............

  1. Capillarity theory

  2. Root pressure theory

  3. Diffusion

  4. Transpiration pull theory

Ans: The correct answer is (d) transpiration pull theory

The transpiration pull theory is the most widely accepted because the water rises in plants through the xylem. Due to reality, this is still mostly accepted today. Water is drawn through roots, not driven through them from below. Even though there is a disadvantage to gravity, two more forces—cohesive and adhesive forces—help to draw the water higher.

3. Water movement between the cells is due to .............

  1. T. P.

  2. W. P.

  3. DPD

  4. Incipient plasmolysis

Ans: The correct answer is (c) DPD

Water movement between cells is due to DPD. Diffusion pressure deficit, often known as DPD, is the force or push that results in the movement of water between the cells in a plant. Compared to the Turgor pressure in the plants, it is high. Because DPD = O.P-T.P.

4. In guard cells, when sugar is converted into starch, the stomatal pore .............

  1. Closes almost completely

  2. Opens partially

  3. Opens fully

  4. Remains unchanged

Ans. The correct answer is (a) Closes almost completely

The starch-sugar interconversion theory states that during the night, sugar transforms into starch in guard cells, raising the osmotic potential. The guard cells expel water, stomata close, and they become flaccid.

5. Surface tension is due to ..............

  1. Diffusion

  2. Osmosis

  3. Gravitational forced

  4. Cohesion

Ans. The correct answer is (d) Cohesion

Due to the cohesion, the surface molecules are attracted to other similar molecules. So the surface tension is due to cohesion. All nearby molecules in a liquid share the cohesive forces that hold them together. Hydrogen bonds are held together by cohesion to provide surface tension on water. Water is drawn toward other molecules by adhesive forces because it is attracted to them.

6. Which of the following types of solution has a lower level of solutes than the solution?

  1. Isotonic

  2. Hypotonic

  3. Hypertonic

  4. An isotonic

Ans. The correct answer is (b) Hypotonic

solutions have lower levels of solutes than solutions. A hypotonic solution contains fewer solutes than an isotonic solution. If a solution's solute concentration is lower than that of a cell, it is referred to in biology as being hypotonic.

7. During the rainy season wooden doors warp and become difficult to open or close because of ...............

  1. Plasmolysis

  2. Imbibition

  3. Osmosis

  4. Diffusion

Ans. The correct answer is (b) Imbibition

During the rainy season, wooden doors absorb water drops due to the wooden doors swelling. So that the answer is imbibition. When water is absorbed by solid colloids, imbibition is a specific sort of diffusion that results in an increase in volume. During the rainy season, humidity rises. Hygroscopic wood absorbs moisture from the air around it. Wood enlarges as a result of this. Therefore, during the wet season, it is challenging to open or close doors constructed of wood.

8. Water absorption takes place through .............

  1. Lateral roots

  2. Root cap

  3. Root hair

  4. Primary root

Ans. The correct answer is (c) Root hair

Mainly plants absorb water from all over the parts of the plant like the root, stem, or leaves. Root hair is more in numbers; these are thin in structure and easily absorb water. So that the answer is root hair.

9. Due to low atmospheric pressure the rate of transpiration will .............

  1. Increase

  2. Decrease rapidly

  3. Decrease slowly

  4. Remain unaffected

Ans. The correct answer is (a) Increase

The rate of transpiration is inversely related to atmospheric pressure; as pressure rises, the rate of transpiration decreases.

10. Osmosis is a property of ..................

  1. Solute

  2. Solvent

  3. Solution

  4. Membrane

Ans: The correct answer is (b) Solvent

Through the process of osmosis, solvent molecules tend to move from a less concentrated solution into a solution that is more concentrated. Any solvent, including gases and supercritical liquids, can go through the osmosis process.

Very Short Answer Type Questions

1. What is osmotic pressure?

Ans: Differing salt concentrations throughout the body are what are responsible for this pressure. The flow of dissolved salts along the concentration gradient is caused by pressure.


2. Name the condition in which the protoplast of the plant cell shrinks.

Ans:  Plasmolysis, which is primarily understood as the contraction of a cell membrane under intense pressure and hypertonic fluid, is ultimately the cause of protoplast shrinkage. Convex or concave plasmolysis are the two forms of plasmolysis that can occur.


3. What happens when a pressure greater than the atmospheric pressure is applied to pure water or a solution?

Ans: Applying pressure values greater than atmospheric pressure indeed causes the water potential of pure water or a solution to increase. As in the case of water diffusing into a plant cell.


4. Which type of solution will bring about deplasmolysis?

Ans:  Determination of DE plasmolysis. The higher concentration of water outside the cell causes water to enter the plasmolysis cell when it is submerged in a hypotonic solution (a solution where the solute concentration is lower than the cell sap).


5. Which type of plants have negative root pressure?

Ans:  It has been established that the peak of transpiration occurs when there is negative pressure. The guard cells and other epidermal cells sag as a result of the water lost through transpiration. In turn, they absorb water from the xylem. As a result, the xylem vessels in the stem and from the surfaces of the leaves to the tips of the roots experience negative pressure or stress.


6. In which conditions transpiration pull will be affected?

Ans:  It has been established that the peak of transpiration occurs when there is negative pressure. The guard cells and other epidermal cells sag as a result of the water lost through transpiration. In turn, they absorb water from the xylem. As a result, the xylem vessels in the stem and from the surfaces of the leaves to the tips of the roots experience negative pressure or stress.


7. Mention the shape of guard cells in Cyperus.

Ans:  It is shown that various environmental factors also affect transpiration. Additionally, light accelerates transpiration by warming the leaf. Without a breeze, the air around a leaf gets more humid, which slows down the rate of transpiration. Diffusion of water out of the leaf occurs more quickly in dry environments.

8. Why do diurnal changes occur in the osmotic potential of guard cells?

Ans: According to starch-sugar interconversion theory (Steward 1964), diurnal changes occur because of starch-sugar interaction.

And according to the theory of proton transport (Levitt-1974), diurnal changes occur due to the transport of proton ions across the cell.

9. What is the symplast pathway?

Ans:  In the symplast, pathway water passes across from one living cell to another living cell from plasmodesmata. The Symplast pathway is the pathway of water movement in the root. It is also referred to as the transmembrane pathway.


Short Answer Type Questions

1. Describe the mechanism for absorption of water.

Ans:  Absorption of water occurs mainly by three processes: imbibition, diffusion, and osmosis.

(1) Imbibition:-

  • Imbibition can be defined as the swelling up of hydrophilic colloids due to the adsorption of water.  

  • Imbibants are substances that absorb water and water that gets imbibed is called an imbibed. 

  • During the process of imbibition, water molecules get tightly adsorbed with the help of root hair cells. 

  • It continues till the equilibrium is reached with the help of water movement along the concentration gradient.

(2) Diffusion:-

  • Diffusion is the process in which an atom/ ion/ molecule moves in a concentration gradient from a higher region of concentration to a lower region of concentration.

  • This movement of atoms/ions/ molecules occurs due to the kinetic energy of molecules.

  • Water moves from higher to lower concentration regions through the permeable membrane of the cell and leads to absorption of water.

(3) Osmosis:-

  • In this process, water enters the cytoplasm by the root hair cell. Root hair cytoplasm contains minerals, sugars, etc. which makes it more concentrated (higher) than outside the cell (lower). 

  • So solvent from lower concentration enters into the cytoplasm of the cell through a semipermeable plasma membrane. 

  • This type of movement is referred to as osmosis.

2. Discuss theories of water translocation.

Ans:  There are many mechanisms/ theories proposed for water translocation such as diffusion, activated diffusion, protoplasmic streaming, electro-osmosis, pressure-flow, etc. But the most convincing theory is Munch’s pressure flow theory or mass flow hypothesis.

  • This theory is proposed by Ernest  Munch. He proposed that a photosynthetic cell synthesizes glucose which increases its osmotic concentration. 

  • Due to this, endo-osmosis occurs which results in water from surrounding cells and the xylem being absorbed and causing the cell to become turgid. 

  • There is an increase in turgor pressure which causes sugar from the photosynthetic cells to be forced ultimately into the sieve tube of the vein. It is called the loading of the vein.

  • At the sink end, the root cell utilizes sugar, which leads to a lowertheotic concentration causing exo-osmosis. Water in the root cell is lost to surrounding cells, which decreases the turgidity of the cell. 

  • Then turgor pressure is lowered, leading to a turgor pressure gradient development. From the sieve tube in the leaf to the root cell. And the food is translocated along the concentration gradient, passively. This is called vein unloading. At the sink end, sugar is used and excess water exudes into the xylem thus translocation occurs.

3. What is transpiration? Describe the mechanism of opening and closing of stomata.

Ans: The loss of water in the form of vapour to maintain the water level in plants is called transpiration. 

  • Stomata help in transpiration. These are the cells that are present in cells consisting of stomata, guard cells, and some accessory cells. 

  • By turgor of guard cells, opening and closing of the stomatal cell are controlled.

  • Guard cells become turgid due to endosmosis in day time due to this turgor pressure is exerted on the thin walls of guard cells. 

  • Guard cell walls are elastic and thin because of this they stretch out. Due to kidney or dumb-bell shape, inner thick walls are exerted out to open the stoma. 

  • Guard cells become flaccid due to exosmosis at night time and because of flaccidity closes the stoma almost. 

  • Endosmosis and exosmosis occur which cause diurnal changes in the osmotic potential of guard cells. And all this leads to the opening and closing of the stomatal pore.

4. What is transpiration? Explain the role of transpiration.

Ans: Transpiration can be defined as the process in which the loss of water in the form of vapour occurs. It occurs through leaves, stems, flowers, and fruits. 

  • Mainly transpiration occurs through the leaves referred to as foliar transpiration.

  • Cuticle, stomata, and lenticels are the three main actual sites for transcription. 

  • According to this, there are three types of transpiration recognized that are cuticular, stomatal, and lenticular.

  • Transcription plays a very important role in maintaining plant rigidity. 

  • It maintains the water level in plants and helps in maintaining osmotic pressure in plants.

  •  It also maintains the turgidity of the cell and thus rigidity is also maintained. 

  • It helps in playing a role in cell division.

5. What is the significance of transpiration? Explain root pressure theory and its limitations.


Significance of Transpiration

  • It helps in removing excess water.

  • Due to this stomata open which is important for gaseous exchange, which leads to photosynthesis.

  • Due to transpiration, the temperature of the leaf surface reduces and causes a cooling effect.

  • Transpiration also helps in the passive absorption of water and minerals from soil.

  • It also helps in maintaining the turgor of cells.

  • Transpiration leads to the ascent of sap.

Root Pressure Theory:

  • Root pressure theory was given by Priestley (1916). Root pressure is a positive pressure that develops in the xylem sap of the root of some plants. 

  • We can say that it is a manifestation of active water absorption. 

  • It favours optimum metabolic activity and reduces transpiration and root pressure is maximum during the rainy season especially in tropical countries and during spring in temperate habitats.

6. Explain the capillarity theory of water translocation.

Ans: This theory states that the physical forces and dead cells are responsible for the ascent of sap. This theory was proposed by Bohem (1863). 

  • According to this theory, when wick dipped in an oil lamp, it shows capillarity due to which oil is raised upwards. 

  • And as it is, the conduction of water in a straw dipped in water, is raised to a certain height.

  • Due to surface tension, forces of cohesion (attraction between like molecules) and adhesion (attraction between unlike molecules) capillarity are shown. 

  • As we can say xylem vessel/ tracheid is comparable to straw. 

  • Due to capillarity water columns exist because of the combined cohesive and adhesive forces of water and the xylem wall. 

  • Water is raised or conducted upwards against gravity, to a few centimetres only because of capillarity. Due to that translocation of water can occur. 

7. Why is transpiration called ‘a necessary evil’?

Ans: Transpiration, which is the loss of extra water in the form of vapour from the aerial portions of the plant, is known as "a necessary evil." The transport of water and nutrients from the root to all other parts of the plant depends heavily on transpiration, but often there can be too much of it, which can cause the leaves to dry up or wilt and cause a loss of soil water.

8. Explain the movement of water in the root.

Ans: A plant's roots and root hair make up its root system. Water from the soil is absorbed by the root hair and diffused to the root. Water entering the roots’ central vascular bundle’s cortex travels through active transportation to the xylem arteries, where it is carried to the various parts of the plant. The cortex is protected by the epiblema.

9. Define and Explain the Terms:

Osmosis, diffusion, plasmolysis, imbibition, guttation, transpiration, the ascent of sap, active absorption, DPD, turgor pressure, water potential, wall pressure, and root pressure.



  • Osmosis is the process by which solvent molecules flow from a section of higher concentration to its region of lower concentration over a semi-permeable wall until equilibrium is achieved. 

  • The isotonic solution, hypotonic solution, and hypertonic solution are the three different kinds of osmosis solutions. 


  • A substance diffuses when it moves from a region of high concentration to one of low concentration. 

  • Because the particles in liquids and gases travel randomly from one location to another, diffusion occurs in these media. 

  • Diffusion is the process through which chemicals enter and exit cells in living things.


  • Plasmolysis is the process through which a plant cell's protoplasm contracts or shrinks as a result of water loss. 

  • Plasmolysis occurs more frequently and in extreme conditions of water loss. Examples of plasmolysis in daily life include:

  • Vegetables shrink under hypertonic circumstances.

  • When blood cells are exposed to hypertonic circumstances, they shrivel. 


  • Imbibition is the term for – anti-water absorption by solid adsorbent particles. For example, dry wood and seeds (such as raisins) can both absorb water.

  • It is the primary and initial step in the absorption of water.

  • The initial stage of seed germination is imbibition.

  • Growing imbibitional pressure allows the seedling to emerge from the soil. 


The loss of water from hydathodes, or tiny holes, on a small herbaceous plant's leaf margin, is known as guttation. It is crucial for plants because through this process, they regulate the quantity of water and nutrients they consume. 


Plants have created a process called transpiration via which water is lost in the form of water vapour from the aerial sections of the plants. Plants, like all living things, need an excretory system to expel excess water from their bodies. 

Ascent of Sap:

  • The movement of water and inorganic elements in the plant from the roots to the leaves is referred to as the ascent of sap. 

  • Transportation is actively influenced by the forces of adhesion and cohesion. The water molecules have a cohesive force. 

  • Water and xylem components are bonded together by an adhesive force. Tall trees can carry water better because of the force caused by transpirational water loss.

Active Absorption:

Active absorption is a process that requires the use of external energy to transfer molecules up a gradient or over an obstruction from an area of lower concentration to a region of greater concentration. Membrane proteins in plants utilise ATP, which is a sort of stored energy, to move molecules through this mechanism of transport.


Diffusion Pressure Deficit is the difference between the diffusion pressures of the solution and its solvent at a specific temperature and atmospheric pressure (DPD). It is equivalent to the difference between a cell's turgor pressure and osmotic pressure.

DPD = OP – TP (Osmotic pressure - Turgor pressure).

Turgor Pressure:

the pressure that the fluid is applying to the cell wall. Termed as hydrostatic pressure. The plasma membrane is forced up against the cell wall. Turgidity refers to the pressure created by the osmotic movement of water. 

Water Potential:

The energy needed to move an extremely small amount of water from the sample to a reference pool of pure free water is known as the water potential. It is the distinction between the water molecule's free energy in a pure solvent and its free energy in a solution. It is denoted as Ψw = Ψs + Ψp.

Wall Pressure:

The wall pressure that the cell wall applies to the turgor pressure. The cell wall pushes against the interior of the cell. The pressure on the wall likewise rises as the turgor pressure rises. It supports a plant's and cells' internal structure.

Root Pressure:

The force that moves fluids upward into the water-conducting vessels of plants is known as root pressure (xylem). This enables a plant to absorb nutrients from the earth and move them to its branches. It is produced by the roots' cells' osmotic pressure. 

10. Distinguish between Osmotic pressure and turgor pressure


              Osmotic Pressure 

                Turgor Pressure

It is the pressure created when water enters or exits a cell via osmosis. It is frequently described as the cell's osmotic potential's negative.

It is the force exerted on the cell wall by the contents of the cells. Depending on the circumstances, it could be either positive or negative.

The cell's osmotic potential, also known as its solute potential, is frequently expressed as the cell's osmotic pressure.

Depending on the circumstance, turgor pressure can be either positive or negative.

11. Enlist macronutrients and micronutrients required for plant growth.

Ans: The macronutrients, which include nitrogen, phosphorus, potassium, and calcium, are those that plants need in huge amounts, whereas the micronutrients, which include iron, zinc, and copper, are only needed in very minute amounts by plants.


12. How are the minerals absorbed by the plants?

Ans: By using apoplast and symplast channels, plants can absorb minerals through diffusion, facilitated diffusion, osmosis, active uptake, or passive uptake. The minerals that need to be absorbed enter the roots in large quantities along the water stream under the influence of transpiration pull, and they are then actively transported, requiring the use of ATP, to be absorbed.


Long Answer Questions

1. Describe the structure of root hair.

Ans: The tiny root hairs, which have an enormous total absorptive surface area and have evolved to help the plant absorb as much water from the soil as possible, are essential to plant survival.

  • The root hair's cell wall offers structural support and defence.

  • The cytoplasm of root hair cells is encased in the cell membrane, which is a semipermeable membrane. the membrane-enclosed vacuole of root hair space, which is normally found in the cytoplasm of a cell and contains fluid and other chemicals.

  • The most crucial component of the root hair, where its activity and growth are based, is the nucleus.


An extended microscopic extension of a root's outer layer of cells, known as root hair, is what allows a root to receive moisture and nutrients from the soil.

Because they have a vast surface area to expedite osmosis, root hair cells are modified for this. It has a nucleus, vacuole, cell wall, and cell membrane.

2. Write on a journey of water from the soil to xylem in roots.


  • Because water molecules adhere to the xylem walls by adhesion and adhere to one another by cohesion, air pressure can pull soil water from the roots up the columns of the xylem to a height of many feet, where these columns of water continue to flow upward. 

  • Osmosis is the initial mechanism by which water enters the root hair cells, creating a root pressure that then extends through the xylem's microscopic tubes. 

  • On the other end of the plant, water either diffuses into the spaces around the photosynthetic cells or leaves the plant through the stomata on the leaves. 

  • This xylem water loss makes it possible for water to travel up the tubes in the xylem, resulting in continuous water movement. 


Through the root system, water travels from the oil to the xylem in the root. Water from the soil is absorbed by the root hair and diffused to the root. Water entering the roots’ central vascular bundle’s cortex travels through active transportation to the xylem arteries, where it is carried to the various parts of the plant. The cortex is protected by the epiblema. 

3. Explain cohesion theory for translocation of water.

Ans: The water potential of the epidermal cells that are in direct contact with the atmosphere decreases as a result of water loss from the leaf to the atmosphere, according to the cohesion theory. 

  • Water moving from adjacent cells along a water potential gradient replaces water lost by epidermal cells, and water moving from tension elements in leaf veins replaces water lost by leaf cells (i.e., xylem elements). 

  • Water in the xylem components of the leaves experiences tension as a result of this part of water circulation.

  • The water is then pushed upward in the shape of a continuous, undisturbed water column until it reaches the transpiring surface at the top of plants. 

  • This part is further conveyed downhill to water in xylem components of the roots through the xylem of the petiole and stem. 

  • Water moves from the earth to the roots because the water potential of root cells is lower than that of the soil.


The foundation of the cohesion theory is the force of cohesion between water molecules, which creates a continuous water column throughout the xylem vessels of the plants from the top to the root. Water is lifted by the lignocellulose that makes up the xylem vessels because of its great attraction for water molecules.

4. Write on the mechanism of opening and closing of the stoma.

Ans: When solutes from nearby epidermal and mesophyll cells enter the guard cells, decreasing their osmotic potential and water potential, the stomata open. 

  • Water can enter guard cells from nearby cells thanks to the reduced water potential and osmotic potential. 

  • The guard cells then become turgid from water buildup, which leads to the guard cells opening. 

  • When the stomata open, the concentration of solutes decreases, which causes the water in the guard cells to diffuse into nearby cells, causing the guard cells to become flaccid and devoid of water. 

  • Stomata closes as a result of them collapsing into one another after that.


The turgor pressure in the guard cells determines when the stomata open and close; when the guard cells swell as a result of water absorption, the stomata open, and when the guard cells contract, the stomata close.

Stomata are open and close as a result of variations in guard cells' turgor. The stomatal orifice is open when these guard cells are turgid, while the stomatal aperture closes when they are flaccid.


5. What is hydroponics? How is it useful in identifying the role of nutrients?

Ans: Without using dirt, hydroponics involves growing plants in nutrient solutions. 

  • Reduced concentrations of oxygen and other minerals may develop in the plant roots because the plant roots are only exposed to a small portion of the solution. 

  • By growing plants without soil and feeding them nutrient-rich water and minerals through their roots, the hydroponic method is one way to satisfy future food needs. 

  • The method is already in use to boost agricultural productivity and grow plants in environments where they otherwise wouldn't be able to survive.


Plants can be grown hydroponically with or without the use of an inert medium, such as soil, to give mechanical support. The roots of plants cultivated hydroponically typically dangle in water that has a rich mixture of nutrients dissolved in it rather than any solid substrate underneath them.

Since hydroponics is practised in enclosed spaces and irrigation and fertilising are carried out mechanically, labour costs are reduced. Huge numbers of vegetables, including peppers, cucumbers, and others, are produced hydroponically.

6. Explain the active absorption of minerals.

Ans: Minerals are actively absorbed in opposition to a concentration gradient. Ions build up in the cell as a result of the constant pumping up of salts. 

  • Similar to how quick cation absorption inhibits other action but increases the absorption of an anion, rapid absorption of an anion delays the absorption of other anions, so boosting the absorption of a cation. 

  • The active absorption necessitates a constant energy outlay. 

  • The ATP produced by root respiration provides this energy. 


Molecules are moved by active transport, which works against a concentration gradient. Energy is required for this procedure. Mineral ions must go into root hair where they are in a higher concentration than in the diluted solutions in the soil for plants to absorb them. The majority of ions are absorbed by meristematic and expanding cells, and this activity requires energy from ATP produced during plant regeneration.


7. Write on macro- and micronutrients required for plant growth.

Ans:  Micronutrient and macronutrient roles:

  • Nitrogen: Nitrogen is an essential element for plants. It is collected from the soil in the form of ions. It is necessary for cell division. It is a key component of hormones, proteins, and other substances.

  • Phosphorous: Phosphorus is essential for several critical activities and is a component of cell membranes, proteins, and nucleic acids. 

  • Potassium: Potassium is a mineral that plants need in significant quantities for growth. It is also necessary for stomata to open and close. It aids in the activation of enzymes and aids in keeping the cell rigid.

  • Calcium:  This mineral is necessary for the proper functioning of the cell membrane as well as cell division. This mineral also regulates metabolic processes.

  • Magnesium: It aids in the production of DNA and RNA and is involved in the activation of enzymes in respiration and photosynthesis. Additionally a crucial component of ribosomes, it aids in ribosome structural maintenance.

  • Sulphur: A crucial component of vitamins, coenzymes, and amino acids.

  • Iron: Compared to other micronutrients, iron is needed in higher concentrations. It aids in the activation of enzymes and is a crucial component of protein. 

  • Manganese: Enzymes involved in respiration, photosynthesis, and other processes are all stimulated by manganese. During photosynthesis, it aids in water splitting.

  • Zinc and Copper: The activation of several enzymes also involves zinc and copper. The operation of the membrane, pollen germination, cell elongation, germination, and other processes are all aided by interstitial fluid. Several enzymes, including nitrogenase, contain molybdenum as a component.

  • Chlorine: Chlorine aids in measuring the anion-cation balance and solute content of the cells.


The nutrients that plants need in the highest concentrations are known as macronutrients. These include calcium, potassium, sulphur, phosphorus, oxygen, hydrogen, and nitrogen. The sources of carbon, hydrogen, and oxygen are air and water, respectively, whereas the sources of the other elements are soil.

Importance of Maharashtra Board Class 12 Biology Chapter 6 Plant Water Relation

Class 12 Biology Chapter 6 is an important part of the botanical section of this syllabus. It explains how a plant absorbs water and retains it. It explains the entire system of a plant beginning from the absorption of water and its retention in different tissues.

This chapter will also explain why plants need water and how they get it. They also need nutrients in the form of minerals absorbed through the water. If we observe carefully, we will find out that water acts as the circulatory system of a plant. It also carries the prepared food from photosynthesis and also enables the removal of excretory products from tissues.

It will also explain the properties of water. It will help you to find out how these properties enable a plant to absorb and retain it in the cells. Class 12th Biology Chapter 6 Solutions will assist you to grab these advanced concepts of cell biology and will enable you to write answers to fundamental questions easily.

Benefits of Maharashtra Board Class 12 Biology Solutions Chapter 6 Plant Water Relation

Now that we have understood the importance of this chapter, we can clearly understand the necessity of water for plants. 

  • These Solutions will explain how water is absorbed in different ways by a plant and how it is transported to the different tissues.

  • The clarification of the concepts will enable you to remember them easily. You can recall them faster and formulate the right answers for the questions coming in the board exams.

  • The use of notes will reduce your preparation time considerably. There is no need to make your own notes when the experts have already covered this chapter for you.

  • Find how the experts have formulated the Plant Water Relations Class 12 questions and answers. They have followed the Maharashtra Board Higher Secondary standards and formulated the answers according to the Class 12 Biology syllabus. It will help you to prepare this chapter properly.

  • Learn the answering skills from the solutions formulated by the experts and score well in the board exams.

Download Plant Water Relation Class 12 Solutions PDF

Get the free PDF version of the solutions for this chapter. You will find accurate answers to all the exercise questions. Check how the experts have explained the concepts in an easier time to complete preparing this chapter. Refer to these notes to clarify doubts and ace the Maharashtra Board board exams.

FAQs on Maharashtra Board Class 12 Solutions for Biology Chapter 6 Plant Water Relation

1. How do plants absorb water?

Plants have specific water-absorbing tissues to soak water from the surroundings. Higher plants have tap root systems. Lower plants have adventitious root systems.

2. What is diffusion?

The movement of solutes such as ions, atoms, molecules, etc inside a mixture or solvent due to differences in concentration is called diffusion.

3. What is osmosis?

Osmosis is the process through which solvent particles move from one system to the other due to the difference in concentration is called osmosis. This process is used by plants to soak water through roots.

4. What is plasmolysis?

The disintegration of the protoplasm of a cell due to its presence in a hypertonic solution is called plasmolysis. Water from the cell comes out due to osmosis causing plasmolysis. 

5. What happens when raisins are soaked in hypertonic solutions?

Raisins get more dehydrated due to the outflow of water to the hypertonic solution.