Which among the following is TRUE regarding the mineral ions in soil?
Option A is the correct answer. Minerals are usually found as ions, charged particles that can conduct electricity. Since they are charged they cannot pass through the charged plasma membrane. So they are actively transported. Also the concentration of minerals in the soil is usually lower than the concentration of minerals in the root. Most of the minerals are actively transported from soil to roots, since most of the minerals are charged particles.
____ have difficulty crossing a charged plasma membrane? (i) NO3- (ii) HPO4- (iii) H2O
NO3- and HPO4-have difficulty crossing a charged plasma membrane.
Why plasmolysed cell appears flaccid. The cell would have ____.
A plasmolysed cell would have lost water and become flaccid.
Plasmolysis usually occurs in ____.
Plasmolysis usually occurs in plant cells.
If the concentration of dissolved solute is more in the surrounding solution than in the cells, then the solution is said to be____.
If the concentration of dissolved solute is more in the surrounding solution than in the cells, then the solution is said to be hypertonic.
Which among the following reduces water potential?
If you add solute to a medium, the water potential decreases favouring endosmosis to occur. Addition of solvent or liquid to a medium causes an increase in water potential, which favours exosmosis.
Which among the following statements is NOT TRUE regarding imbibition?
Imbibition can cause increase not reduce in the volume of solids.
An equivalent of a plasmolysed cell is a ____.
An equivalent of a plasmolysed cell is a shrivelled animal cell.
____ causes plasmolysis.
Exosmosis causes plasmolysis.
Which among the following is created by osmotic pressure of the xylem sap?
Root pressure is created by osmotic pressure of the xylem sap. So option C is the correct answer.
Which among the following statements is NOT TRUE regarding water absorption in plants?
Water is usually absorbed along with the minerals by the roots.
Which among the following is NOT TRUE about Osmosis?
Osmosis tries to decrease, not increase the concentration gradient between the two solutions.
What happens if you remove a band of bark around a tree trunk?
If you remove a band of bark around a tree trunk, the process does not interfere with the upward flow of water. This is because removing only the bark removes only the phloem tissue and not the xylem tissue. So the leaves do not wilt as they get water. However, the plant dies eventually, since the roots do not get food from the leaves due to the absence of phloem. So option B is the correct answer.
Deplasmolysis is a process of ____.
Deplasmolysis is a process of recovery of a plasmolysed plant cell.
Which among the following is NOT TRUE regarding osmotic pressure?
Osmotic pressure is always a positive pressure.
Which among the following DOES NOT describe "translocation of minerals" in plants?
Calcium is usually stored in plants. The minerals that are often mobilised in plants are phosphates, carbonate and nitrates. So option D is the correct answer.
Which among the following is not needed for mineral absorption in plants?
Phloem is not required for mineral absorption. Some mineral ions from soil cannot easily pass through the cell membrane of root cells. So energy is required by root cells for absorbing mineral ions from soil. Ions are dissolved in water, so water is required to transport mineral ions. Xylem is required to transport water and minerals in plants. So option A is the correct answer.
What is the purpose of "ringing experiment"?
When you place a girdled twig in a beaker of water, the upper leaves of the shoot remain turgid and this indicates that water is still moving upwards the xylem. This experiment is called "ringing experiment". The ringing experiment is done to show the path of ascent of the sap.
Water potential due to solute concentration is also called ____.
Water potential allows water molecules to move from a hypotonic solution to a hypertonic solution across a semi-permeable membrane.
Which among the following parts in roots absorb water and mineral ions?
Root hairs are extensions of the epidermal cells. They have thin cell walls so that water and mineral ions can easily be absorbed from the soil. So option B is the correct answer.
Which among the following is TRUE about mineral uptake by the roots?
Root hairs take up ions from the soil into the cytoplasm of the epidermal cells both by active and passive transport. The transport proteins embedded in the plasma membrane of the endodermal cells allow only some solutes. Water, along with the ions, is osmotically taken up by the root hairs. So option A is the correct answer.
Which among the following statements is FALSE regarding water potential in plants?
Water always moves from region of higher water potential to lower water potential.
If you see the leaves of grass in early morning, you would notice tiny droplets on the tip of grass leaves. This is called____, which is a result of root pressure.
Guttation is water loss that occur due to root pressure, whereas transpiration is water loss due to evaporation. During photosynthesis, water is lost to produce food. During cellular respiration, water is produced, not lost.
Root hairs are the extensions of root ____ cells.
Epidermis is the outermost layer of the roots. The cells of the epidermis protrude outward to form the root hairs.
If you place a plant cell in a solution that has low water potential, ____.
A solute with low water potential has high solute concentration. So when a plant cell is placed in a solution with low water potential, then it lose water by osmosis.
How are K+ ions absorbed in plants?
K+ ions are absorbed chemiosmotically, since they cannot pass through the charged plasma membrane of root cells. So option B is the correct answer.
Osmosis can be defined as ____.
Osmosis is the movement of solvent particles (water molecules) from a region of lower solute concentration or higher solvent concentration to the region of higher solute or lower solvent concentration.
Which among the following statements is NOT TRUE regarding the role of soil in water absorption by plants?
If soil holds water, the roots will absorb more water.
____ in the roots is chiefly responsible for forcing water from soil to the roots and then into the plant body.
A high concentration of minerals inside the root cells than in the soil creates root pressure. This root pressure forces water up out of the root to other plant parts.
Share your Results: