(a) Hypertonic salt solution (b) Hypotonic salt solution. (a) Hypertonic salt solution (b) Hypotonic salt solution
Show by a series of diagrams, the change which a plant cell will undergo when placed in
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Absorption by Roots – The Process Involved
Study the experimental setup in the figure and then answer the questions that follow.
(a) What phenomenon is being studied by this setup? (b) Explain the phenomenon mention in (a) above. (c) What is meant by ‘semipermeable membrane’? (d) What will you observe in the setup after about...
A candidate in order to study the process of osmosis has taken 3 potato cubes and put them in 3 different beakers containing 3 different solutions. After 24 hours, in the first beaker the potato cube increased in size, in the second beaker the potato cube decreased in size and in the third beaker, there was no change in the size of the potato cube. The following diagram shows the result of the same experiment.
1. Give the technical terms of the solutions used in the beakers 1, 2 and 3. 2. In beaker 3, the size of the potato cube remains the same. Explain the reason in brief. 3. Write the specific features...
A leaf cell of a water plant was placed in a liquid other than pond water. After sometime, it assumed a shape as shown below:
(a) Give the term for the state of the cell it has acquired. (b) Comment on the nature (tonicity) of the liquid surrounding the cell. (c) Redraw in the space provided, the diagram of the cell if it...
The diagram given below represents an experimental set-up to demonstrate a certain process. Study the same and answer the questions that follow:
(a) Name the process. (b) Define the above-named process. (c) What would you observe in the experimental set-up after an hour or so? (d) What control experiment can be set up for comparison? (e)...
The diagram below represents a layer of epidermal cells showing a fully grown root hair. Study the diagram and answer the questions that follow:
1. Name the parts labelled A, B, C and D. 2. The root hair cell is in a turgid state. Name and explain the process that caused this state. 3. Mention one distinct difference between the parts...
Two potato cubes each 1 cm3 in size, were placed separately in two containers (A and B), the container A having water and the other (B) containing concentrated sugar solution. After 24 hours when the cubes were examined, those placed in water were found to be firm and had increased slightly in size and those placed in concentrated sugar solution were found to be soft and somewhat decreased in size. Use the above information to answer the questions that follow:
1. Account for the firmness and increase in the size of the potato cubes placed in water. 2. Account for the softness and decrease in size of the potato cubes which were placed in sugar solution. 3....
Study the diagram given below and answer the questions that follow:
1. Name the process being studied in the above experiment. 2. Explain the process mentioned in (a) above 3. Why is oil placed over water? 4. What do we observe with regard to the level of water when...
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?
The extraction of mineral nutrients is higher within the root hairs than in the surrounding soil because the absorption of mineral nutrients in the soil involves the active transport of cells....
Explain how soaked seeds swell up and burst their seed coats.
Imbibition is the absorption of water by substances such as cellulose (cell wall) and starch. Turgor pressure set within plant cells due to hydrostatic pressure on cell walls caused by water...
Leaves of the sensitive plant wilt and droop down on a slight touch. What mechanism brings about this change?
The rapid pull of the leaves of the delicate plant (Mimosa pudica) is a prime example of the turgor movement. When one of the leaves is touched, even slightly so, the leaflets are rolled back and...
What is transpiration pull? How is it caused?
As water is lost from the surface of the leaf through transpiration, many water molecules are pulled upwards due to the tendency of the water molecules to stay compacted (converting), and thus to...
The following diagram represents a plant cell after being place in a strong sugar solution.
Guidelines 1 to 5 indicate the following: (1) Cell Wall (2) Strong Sugar Solution (3) Protoplasm (4) Large Vacuole (5) Nucleus (a) What is the state of the cell shown in the diagram? (b) Name the...
Explain the mechanism of the closing and opening of the stomata.
Closing and opening of the stomata depends on the strength of the alert cells. Each guard cell has a thick wall on one side facing the stoma and a small wall on the other side. The guard cells...
Give two examples of turgor movements in plants.
1. Mimosa pudica is a prime example of the turgor movement. The rapid fall of the leaves of sensitive plants. When one of the leaves is touched, even slightly so, the leaflets are rolled back and...
Mention whether the following statements are true (T) or false (F) and give explanation in support of your answer.
(a) Plasmolysis is reverse of deplasmolysis. (b) Guttation is another name for bleeding in plants. (c) Soaked seeds burst three seed coats. (d) If the phloem of a twig is removed keeping the xylem...
Give reasons for the following:
1. If you sprinkle some common salt on grass growing on a lawn, it is killed at that spot. 2. If you uproot a plant from the soil, its leaves soon wilt. 3. It is better to transplant seedlings in a...
What is the difference between flaccid and turgid? Give one example of flaccid condition in plants.
FlaccidTurgidThe state in which the cell content is shrunken is called flaccidity. These cells are referred to as flaccid.The condition in which the cell wall is rigid and stretched due to the...
Complete the following statements:
1. Hypotonic solution is one in which the solution kept outside the cell has lower solute concentration than __________ the cell. 2. Active transport is one in which the ions outside the roots move...
Fill in the blanks by choosing the correct alternative from those given in brackets:
1. When placed in a more concentrated solution, the cell contents will ……….. (Shrink/swell up) 2. The pressure by which the …………. molecules tend to cross the semi-permeable membrane is called...
Match the items in column I those in column II
Column IColumn IIXylemsemi-permeablePhloempermeableCell membranedownward flow of sapRoot pressureupward flow of waterCell wallguttation Answer: Column IColumn IIXylemupward flow of...
Differentiate between the following:
(a) Plasmolysis and deplasmolysis (b) Turgor pressure and wall pressure (c) Guttation and bleeding(d) Turgidity and flaccidity (a) Plasmolysis and deplasmolysis PlasmolysisDeplasmolysisWhen placed...
(a) Mention whether the following statements are true (T) or false (F). (b) Correct the false statements by altering the last word only.
1.A plant cell placed in hypotonic solution gets plasmolysed. (T/F) 2. Addition of salt to pickles prevents growth of bacteria because they turn turgid. (T/F) 3.Cells that have lost their...
Give the equivalent terms for the following:
1. Pressure exerted by the cell contents on the cell wall. 2. The condition in which the cell contents are shrunken. 3. Loss of water through a cut stem. Answers: Turgor pressure 2. Flaccidity 3....
Name the following:
1. The condition of a cell placed in a hypotonic solution. 2. The process by which intact plants lose water in the form of droplets from leaf margins 3. Process by which water enters root hairs. 4....
The most appropriate characteristic of semi-permeable membrane is that
a) it has minute pores b) it has no pores c) it allows the solute to pass through but not the solvent d) it allows a solvent to pass through freely but prevents the passage of the solute Answer: d)...
What is responsible for guttation?
a) Osmotic pressure b) Root pressure c) Suction pressure d) Capillarity Answer: b) Root pressure
The space between the cell wall and plasma membrane in a plasmolysed cell is filled with
a) isotonic solution b) hypotonic solution c) hypertonic solution d) water Answer: d) water
The highest water potential (capacity to move out to higher concentrated solution) is that of
a) Pure water b) 10% salt solution c) Honey d) 50% sugar solution Answer: a) Pure water
Osmosis and diffusion are the same except that in osmosis there is
a) a freely permeable membrane b) a cell wall in between c) a selectively permeable membrane in between d) an endless inflow of water into a cell Answer: c) a selectively permeable membrane in...
Which one of the following is a characteristic NOT related with the suitability of the roots for absorbing water?
a) Tremendous surface area b) Contain cell sap at higher concentration than the surrounding water c) Root hairs have thin cell walls d) Grow downward into the soil Answer: d) Grow downward into the...
Movement of molecules of a substance from the region of their higher concentration to the region of their lower concentration without the involvement of a separating membrane, is called:
a) Osmosis b) Diffusion c) Active transport d) Capillarity Answer: b) Diffusion
The state of a cell in which the cell wall is rigid and stretched by the increase in volume due to the absorption of water is called
(a) Flaccidity (b) Turgidity (c) Capillarity (d) Tonicity Answer: (b) Turgidity
A plant cell placed in a certain solution got plasmolysed. What was the kind of solution?
(a) Isotonic sugar solution (b) Hypotonic salt solution (c) Hypertonic salt solution (d) Isotonic salt solution Answer: (c) Hypertonic salt solution
Absorption of water by the plant cells by surface attraction is called:
(a) Diffusion (b) Osmosis (c) Imbibition (d) Endosmosis Answer: (c) Imbibition