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The cell is said to be turgid when the plant cell wall becomes rigid and stretched by an increase in the volume of vacuoles due to the absorption of water when placed in hypotonic solution. On the other hand, the cell is said to be flaccid when the cell contents get shrunken when the cell is placed in hypertonic solution and the cell is no more tight. Flaccidity is the reverse of turgidity.

Example: Weeds can be killed in a playground by sprinkling excessive salts around their base.

Or

A plant cell when immersed in hypertonic solution like salt solution for about 30 minutes will become flaccid or limp.

The cell wall and plasma membrane in a plasmolysed cell is filled with-

(d) water

Saliva is mainly produced by three pairs of salivary glands, the parotids (cheek), the sub-maxillary/sub-mandibular and the sub linguals. These glands are situated just outside the buccal cavity and secrete salivary juice into the buccal cavity.

(a) Pure water

(a) The cell is flaccid i.e. it is plasmolysed.

(b) Plasma Membrane

(c) Plasmolysis would not occur and flaccidity would not be seen i.e. the protoplasm would not have shrunken away from the cell wall.

(d) Cell Wall is absent in animal cell.

c) Imbibition

(a) the fluids inside

(b) transported inside against their concentration gradient

(c) turgor movements

(a) Turgidity

(b) Guttation

(c) Osmosis

(d) Xylem

(e) Endosmosis

(f) Diffusion

(g) Root pressure

(d) it allows a solvent to pass through freely but prevents the passage of the solute

(a) True. 

Plasmolysis occurs due to outflow of water from the cell when placed in hypertonic solution due to which the cytoplasm shrinks away from the cell wall. On the other hand, deplasmolysis is the result of the re-entry of water into the plasmolysed cell when placed in hypotonic solution due to which the protoplasm again swells up pressing tight against the cell wall.

(b) False. Guttation is the process by which drops of water appear along leaf margins due to excessive root pressure whereas bleeding is the loss of cell sap through a cut stem.

(c) False. There is only one seed coat in a seed.

(d) False. The leaves of the twig remain turgid since its xylem is intact and xylem is responsible for water conduction in plants.

(e) False. Guttation occurs due to excessive root pressure. It is maximum when root pressure is maximum which occurs in the early mornings or at night. This is because during these times, transpiration is very low and water absorption is very high.

(f) False. Dry seeds when submerged in water swell up due to imbibitions. On contact with water dry seeds imbibe water and swell up.

(d) Grow downward into the soil

Examples of turgor movements in plants:

(i) In Mimosa pudica, a sensitive plant, the stimulus of touch leads to loss of turgor at the base of the leaflets and at the base of the petioles called pulvinus. This causes the folding and drooping of leaves of the plant.

(ii) The leaves of insectivorous plants close up to entrap a living prey. When the insect come in contact with the leaf, it loses it turgor hence closing the leaves of the plant. 

(iii) The bending movements of certain flowers towards the sun.

(Any two)

BWe is non enzymatic.

If the concentration of mineral nutrient elements is higher inside the root-hairs than in the surrounding soil, then roots take them in from the soil by 'active transport'. In active transport, the mineral ions are forcibly carried from the surrounding soil i.e. the region of their lower concentration into the roots i.e. the region of their higher concentration through the cell membrane by expenditure of energy. This energy is supplied by the cell in the form of ATP.

When soaked in water, the seeds swell up due to imbibition and endosmosis. During these two processes water enters the cell. Due to endosmosis, at some point, the seed coat is unable to bear the turgor pressure and hence, the seed coat bursts.