0

Transport of molecules - class-XII

Attempted 0/64 Correct 0 Score 0

If two solution have the same osmolarity, they are said to be

  1. Hypertonic

  2. Hypotonic

  3. Isotonic

  4. None of the above


Correct Option: C
Explanation:

Isotonic means two solutions having the same osmolarity. It allows the free movement of water across the membrane without changing the solute concentration. Hypotonic surrounding solution means a solution with less osmolarity. This means that concentration of solutes is less in the surrounding medium, than the concentration of solutes in cell sap and hypertonic surrounding solution means the concentration of solutes is more than the concentration of solutes in the cell sap.

The space between the plasma membrane and the cell wall of a plasmolyzed cell surrounded by a hypertonic solution is occupied by the

  1. Hypotonic solution.

  2. Isotonic solution.

  3. Hypertonic solution.

  4. Water.


Correct Option: C
Explanation:

A plant cell wall is fully permeable and it cannot regulate the entry or exit of a solution. When a plant cell is placed in a hypertonic solution it will lose water by exosmosis. This process is called plasmolysis. The protoplasm will shrink and will move inwards and away from the cell wall. As a result, the hypertonic solution will occupy the space between the plasma membrane and the cell wall. Thus the correct answer is option C.

All the following involves osmosis except.

  1. Water from soil entering a root hair

  2. Water passing from root hair to adjacent cells

  3. Water passing up a xylem vessel element to xylem vessel element above it

  4. Water entering a mesophyll cell from xylem vessel element


Correct Option: A

At the time of opening of stomata, pH of guard cells in comparison to pH of subsidiary cells, is?

  1. Higher

  2. Lower

  3. Equal

  4. Uncertain


Correct Option: A

Two cells A and B are contiguous. Cell A has osmotic pressure $10$atm, turgor pressure $1$ atm and diffusion pressure deficit $3$ atm. Cell B has osmotic pressure $8$ atm, turgor pressure $3$ atm and diffusion pressure deficit $5$ atm. The result will be?

  1. Movement of water from cell B to A

  2. No movement of water

  3. Equilibrium between the two

  4. Movement of water from cell A to B


Correct Option: A

When a plant cell is placed in a solution which is hypotonic to the cell sap, which of the following conditions will not apply

  1. The water potential of the cell sap will rise

  2. The suction pressure of the cell sap will fail

  3. The cell will become turgid

  4. The wall pressure of the cell will fail


Correct Option: D
Explanation:

If a cell is placed in hypotonic solution, water start moving into the cell by the process of endosmosis and cell become turgid.

Ephemerals are drought ___________.

  1. Loving

  2. Enduring

  3. Escaping

  4. Resistant


Correct Option: C

All the following involve osmosis except.

  1. Movement of water from soil to root

  2. Movement of water from root hair to endodermis and pericycle

  3. Movement of water between xylem elements

  4. Movement of water form xylem to mesophyll cell of leaves


Correct Option: A

Consider the following events involved in stomatal opening:
1. Turgor pressure of guard cells increases
2. $K^+$ ions move into guard cells
3. pH of guard cells decreases
4. Water moves into guard cells
What is the correct sequence of these events leading to stomatal opening:

  1. 2-4-3-1

  2. 3-2-4-1

  3. 2-3-4-1

  4. 3-1-2-4


Correct Option: A

Choose the correct answers from the alternatives given :
The osmotic pressure of pure water is

  1. 0

  2. 0.1

  3. 1

  4. 10


Correct Option: A
Explanation:

Osmotic pressure is the minimum pressure applied to prevent the inward flow of solvent molecules from a dilute solution into the concentrated solution, where both solutions are separated by a semipermeable membrane. 

The osmotic pressure would be zero if pure water were on both sides of the semi-permeable membrane. 

So the correct answer is "0"

Active transport from outside to inside of molecule across a membrane requires

  1. Cyclic AMP

  2. Acetyl chlorine

  3. ATP

  4. Phloroglucinol


Correct Option: C
Explanation:

Active transport from outside to the inside of molecules across a membrane requires ATP. It is required in transferring solutes across the membrane may be through an ATPase which creates ph gradient across the membrane. Thus, the correct option is C.

ATP molecules combine with carrier molecules and allow passage of substances.

  1. Along concentration gradient

  2. Against concentration gradient

  3. Both A and B

  4. ATP is not required


Correct Option: B
Explanation:

In the active transport, there is a movement of some substance from low concentration to the high concentration i.e., against the concentration gradient wit the help of ATP combined with carrier molecules.

Thus, the correct answer is option B.

All mineral salts absorbed in cells are

  1. Ions

  2. Atoms

  3. Molecule

  4. All of the above


Correct Option: A
Explanation:

All mineral salts are present in soil as charged ions adsorbed to clay particles. The minerals are absorbed in charged forms and not in uncharged forms through the exchange process. Thus, the correct answer is option A.

Glucose and amino acids are absorbed in the intestine by

  1. Active transport

  2. Passive transport

  3. Selective absorption

  4. Osmosis


Correct Option: A

In which one of the following, expenditure of energy is required?

  1. Osmosis

  2. Diffusion

  3. Active transport

  4. Passive transport


Correct Option: C
Explanation:

Active Transport uses energy to pump molecules against a concentration gradient and is carried out by membrane proteins.

Which of the following means of transmembrane transport involves the expenditure of energy by the cell and can move materials up a concentration gradient?

  1. Osmosis

  2. Facilitated diffusion

  3. Simple diffusion

  4. Active transport


Correct Option: D
Explanation:
In one form of transport across the cell membrane, ATP is utilized. The utilization of an ATP molecule provides the cell with an energy boost which enables the transport of different molecules across the cell membrane. This is termed as active transport of molecules across the cell membrane.
So, the correct answer is 'Active transport'.

Decreasing order concentration of minerals inside cell is

  1. Ca$^{+2}$$-$K$^+$$-$Na$^+$.

  2. K$^+$$-$Ca$^{+2}$$-$Na$^+$.

  3. K$^+$$-$Na$^+$$-$Ca$^{+2}$.
  4. Na$^+$$-$K$^+$$-$Ca$^{+2}$.


Correct Option: C
Explanation:
Potassium ions are usually higher inside the cell than outside the cell, and its concentration inside the cell is about 10 to 30 fold higher than the other components, while sodium ion is higher outside the cell than inside the cell. 
So, the answer is C.

Choose the correct answer from the alternatives given.
Active transport

  1. Requires an input of ATP

  2. Is involved in diffusion

  3. Occurs in osmosis and facilitated transport

  4. All of the above


Correct Option: A
Explanation:
In one form of transport across the cell membrane, ATP is utilized. The utilization of an ATP molecule provides the cell with an energy boost which enables the transport of different molecules across the cell membrane. This is termed as active transport of molecules across the cell membrane.

So, the correct answer is 'Requires an input of ATP'.

Energy is required for

  1. Active transport

  2. Facilitated transport

  3. Diffusion

  4. All of these


Correct Option: A
Explanation:
In one form of transport across the cell membrane, called active transport, ATP is utilized. The utilization of an ATP molecule provides the cell with an energy boost which enables the transport of different molecules across the cell membrane.
So, the correct answer is 'Active transport'.

Choose the correct answer from the alternatives given.
Which of the following processes requires the greatest expenditure of energy by the cell?

  1. Facilitated diffusion

  2. Diffusion

  3. Active transport

  4. Osmosis


Correct Option: C
Explanation:
In one form of transport across the cell membrane, ATP is utilized. The utilization of an ATP molecule provides the cell with an energy boost which enables the transport of different molecules across the cell membrane. This is termed as active transport of molecules across the cell membrane.

So, the correct answer is 'Active transport'.

Substances like glucose, amino acids, Na$^+$ etc in filtrate are reabsorbed by

  1. Passive transport

  2. Active transport

  3. Both active and passive transport

  4. Facilitated diffusion


Correct Option: B
Explanation:

In cellular biology, active transport is the movement of molecules across a membrane from a region of their lower concentration to a region of their higher concentration—against the concentration gradient. Active transport requires cellular energy to achieve this movement. There are two types of active transport: primary active transport that uses ATP, and secondary active transport that uses an electrochemical gradient. An example of active transport in human physiology is the uptake of glucose in the intestines. So substances like glucose, amino acids, sodium ions in filtrate are reabsorbed by active transport.


So the correct option is 'Active Transport'.

ions are absorbed from the soil by

  1. Passive transport

  2. Active transport

  3. Both (1) & (2)

  4. Imbibition


Correct Option: B
Explanation:

Minerals are absorbed from the soil in the form of ions. Absorption of minerals and water are two different processes but the  pathway is same. Mineral ions cannot be absorbed by osmosis or diffusion because the concentration is low. So the root hair cells have carrier molecules on their surface which pick the ions and move against the concentration gradient. Since the movement is against the concentration gradient then ATP will be required. So The absorption of ion is a Active process. 


So, the correct answer is 'Active transport'.

${ Na+K }^{ + }$ pump represents

  1. Active transport

  2. Passive transport

  3. Osmosis

  4. Simple diffusion


Correct Option: A
Explanation:

The sodium-potassium pump is a specialized mechanism to transport proteins using energy. The process of moving sodium and potassium ions across the cell membrane is an active transport as it involves the hydrolysis of ATP. The hydrolysis of ATP molecule provides the necessary energy for the transport of molecules across the membrane. The action involves an enzyme known as Na+/K+-ATPase.

So, the correct answer is 'Active transport'.

The movement of a molecule across a typical plant cell about 50mm takes aproximately

  1. 2.5m

  2. 2.5 h

  3. 2.5s

  4. none of these


Correct Option: D
Explanation:

Lines of stomates (shown by the orange colour of the guard cells) lie along the flanks describe the status and movement of water in plants, soil and the atmosphere. This internal hydrostatic pressure (also called turgor pressure) is typically 0.5 away from the cell wall, and solution with small molecular weight solutes. 

So, the correct option is "D" (None of these).

What happens when wilted vegetable are dipped in water _________________.

  1. They regain their size

  2. Remain to be same

  3. Colour will change

  4. Decrease in size because of lose of water.


Correct Option: A
Explanation:

  • After dipping into water wilted vegetable regain their size, as water travells through a network of veins through out the plant and cell are hydrated and refirm their size. by a process called osmosis .
  • Leaves turn yellow or red when they falls , in fallpalnt breakdown and reabsorb chlorophyll, letting the colours of other pigments show through , hence colour changes.
  • When vegitables are wilted due to  dehydration, their size decreases due to loss of water.
 So the correct answer is " They regain their size".

Which one of the following is the correct statement for an active sodium-potassium ATPase ?

  1. It pumps out 3 Na-ions and pumps in 2 K-ions

  2. It pumps out 3 Na-ions and pumps in 3 K-ions

  3. It pumps out 3 Ca-ions and pumps in 2 K-ions

  4. It pumps out 3 Na-ions and pumps in 2 Ca-ions


Correct Option: A
Explanation:

Sodium-potassium pump is important to produce action potential by nerve cells. As it transport of three Na+ to the outside of the cell and the transport of two K+ ions to the inside. This changes the membrane potential on the inside, making the inside of the cell more negative or hyperpolarized, which leads to forward movement of electric impulse

So, the correct answer is 'It pumps out 3 Na$^+$and pumps in 2 K$^+$ '

The absorption of water due to expenditure of energy is called as ____________.

  1. Active absorption

  2. Non-smotic absorption

  3. Passive absorption

  4. All of the above


Correct Option: A
Explanation:

 It is called water absorption 'through roots', rather 'by' roots. It occurs in rapidly transpiring plants during the daytime, because of the opening of stomata and the atmospheric conditions. The force for absorption of water is created at the leaf end i.e. the transpiration pull.

Active transport

  1. Releases energy

  2. Requires energy

  3. Produces ATP

  4. Produces a toxic substance


Correct Option: B
Explanation:

There are two types of absorption mechanisms i.e., active and passive transport. Active transport is the movement of solute or solvent molecules against the concentration gradient. It requires the expenditure of energy in the form of ATP. Thus, the correct answer is option B.

Carrier protein helps in

  1. Transport of ions across the membrane

  2. Passive ions absorption

  3. Water absorption

  4. Vaporization


Correct Option: B
Explanation:
Carrier proteins help in passive movement of molecules across the plasma membrane
Example GLUT, aquaporin etc
So, the correct answer is 'Passive ions absorption'

Active transport across cell membrane requires

  1. Glucose

  2. Steroids

  3. Energy in the form ATP

  4. Proteins and glucose


Correct Option: C
Explanation:

In active transport, substances move against a concentration gradient across a cell membrane. Hence energy is required. The energy available in the body in the form of ATP is used to move this substance across the cell membrane. Thus the correct answer is option C.

Movement of ions r molecules against electrochemical gradient is called ______________.

  1. Pinocytosis

  2. Diffusion

  3. Active transport

  4. Brownian movement


Correct Option: C

Active absorption is affected by:

  1. Osmotic concentration

  2. Associate tissue structures

  3. Transpiration

  4. Sucking capacity of root hair


Correct Option: A
Explanation:

Active absorption refers to absorption against the concentration gradient. Absorption of a solute from a region of low concentration to a region of higher concentration by the help of energy, is called active absorption. Hence, active absorption depends on osmotic concentration.

Active transport involves the transport of molecules across a cell membrane.
In order to establish and maintain a concentration gradient, which of the following condition is suitable?

  1. Free energy is used to drive molecules back-and-forth across the transmembrane protein.

  2. Free energy is used to drive molecules and across a transmembrane protein against the concentration gradient.

  3. No free energy is required.

  4. There must be an equal quantity of molecules on both sides of the membrane.


Correct Option: B
Explanation:

Free energy obtained from hydrolysis of ATP is used for the movement of solutes against their concentration gradient across the plasma membrane using a transport transmembrane protein also called pump

So, the correct answer is 'Free energy is used to drive molecules and across a transmembrane protein against the concentration gradient'

In the light of carrier concept, the transport of ion across the membrane against concentration gradient is

  1. Passive process

  2. Non-osmotic process

  3. Osmotic process

  4. Active process


Correct Option: D
Explanation:

According to carrier concept for transport of ion in plants, transport is mediated by specific carriers. When the ion is transported against the concentration gradient, the ion carrier is activated in presence of ATP and a kinase enzyme. The activated carrier forms a complex with an ion at the outer surface and transported in. Because this process involves ATP, hence, it is called active process.

Carrier proteins are involved in the

  1. Active transport of ions

  2. Passive transport of ions

  3. Water transport

  4. Both A and B


Correct Option: D
Explanation:

Active transport is the movement of a substance across a membrane against its concentration gradient. Unlike channel proteins which only transport substances through membranes passively, carrier proteins can transport ions and molecules either passively through facilitated diffusion, or via secondary active transport.

Therefore D is the correct option. 

Active transport across biomembrane involves

  1. Production of ATP

  2. Requirement of energy

  3. Production of toxin

  4. Release of energy


Correct Option: B
Explanation:
  • Active transport is a process by which molecules move across the cell membrane from a region of low concentration to a region of high concentration against the concentration gradient using energy.
  • This energy requirement is fulfilled by the ATP molecules (metabolic energy).
  • The substances which are transported across the cell membrane by active transport are- Na+, K+, Mg2+, and Ca2+.
  • So, the correct answer is 'Requirement of energy'.

Minerals are absorbed by the plants, through

  1. Pressure flow

  2. Diffusion

  3. Active transport

  4. Osmosis


Correct Option: C
Explanation:

Minerals are absorbed by plants through active transport as minerals are present in the soil mostly in the form of charged particles which fail to move across cell membrane and concentration of minerals in the cell is usually greater than that present in the soil solution. Therefore, most of the minerals are absorbed by active mechanism involving expenditure of energy in the form of ATP.

Hence, C is the correct answer.

$Na^+ / K^+$ pump in a cell is an example of

  1. Osmosis

  2. Diffusion

  3. Passive transport

  4. Active transport.


Correct Option: D

Active transport of ions by a cell requires

  1. High temperature

  2. Low temperature

  3. Alkaline pH

  4. ATP


Correct Option: D
Explanation:
  • Active transport can be defined as the movement of molecules and ions across a cell membrane from a region of lower concentration (of the molecules) to the region of higher concentration i.e, movement of molecules occurs against the concentration gradient. 
  • This transport requires cellular or metabolic energy which is available in the form of ATP molecules produced within the cell.
  • So, the correct answer is 'ATP'.

Which is not true of active transport

  1. It is chemical process

  2. Energy is obtained from ATP

  3. Occurs through carrier molecules

  4. Not modified by enzymes.


Correct Option: A

Active transport is characterised by

  1. Requires special membrane proteins

  2. Highly selective

  3. Requires ATP energy

  4. All of the above


Correct Option: D
Explanation:
  • Active transport can be defined as the movement of molecules or ions across a plasma membrane from a region of lower concentration (of molecules or ions) to a region of higher concentration, against the concentration gradient. 
  • For this cellular energy is required which is available in the form of ATP molecule and enzymes.
  • So, the correct answer is 'All of the above'.

It is not characteristic of active transport

  1. Highly selective

  2. Insensitive to inhibitors

  3. Uphill transport

  4. Transporter saturates.


Correct Option: B

The energy is required in absorption of water by

  1. Active absorption

  2. Passive absorption

  3. Both passive and active absorption

  4. None of the above


Correct Option: A
Explanation:

Absorption of water takes place by both active and passive absorption.
Water, as per some theory, is absorbed against the concentration gradient. This type of absorption is termed active absorption where the movement is against the concentration gradient and requires energy in the form of ATP.

Most of the plants observe passive absorption, meaning, the movement is without utilization of metabolic energy. 
Thus, the correct answer is option (C). 

Glucose and amino acids are absorbed in intestine by

  1. Osmosis

  2. Passive transport

  3. Active transport

  4. Selective absorption


Correct Option: C
Explanation:

The monosaccharides glucose and galactose are transported into the epithelial cells by common protein carriers via secondary active transport I.e  by co-transport with sodium ions. The monosaccharides leave these cells via facilitated diffusion and enter the capillaries through intercellular clefts.

Thus C is the correct option. 

Movement of materials against concentration gradient is achieved by

  1. Active trasnport

  2. Passive transport

  3. Diffusion

  4. Osmosis


Correct Option: A
Explanation:

  • Active transport is the transport where the direct expenditure of energy takes place and the molecules move against the gradient which is from lower concentration to the higher concentration.
  • Passive absorption is the absorption which takes place without expenditure of energy. The water molecules move from higher concentration to the lower concentration which is towards the gradient. 
  • In diffusion, the ions or molecules randomly diffuses the semipermeable membrane along the concentration gradient.
  • Osmosis is the process of diffusion of molecules from the region of higher concentration to the lower concentration through a semipermeable membrane. 
So, the correct answer is option A.

State whether the following statements are true or false.
Carrier proteins are necessary for active transport to occur.

  1. True

  2. False


Correct Option: A
Explanation:

Carrier proteins are those which facilitate diffusion of molecules across the cell membrane, they allow movement of molecules in and out of the cells against the concentration gradient. Active transport requires carrier proteins also called as pumps. They need ATP energy because the transport is uphill, against the concentration gradient.

So, the correct answer is 'True'. 

Choose the correct answer from the alternatives given.
The sodium potassium pump moves sodium and potassium ions across the plasma membrane by

  1. Facilitated transport

  2. Active transport

  3. Cotransport

  4. Endocytosis


Correct Option: B
Explanation:

The sodium-potassium pump in a cell membrane works via active transport. It uses a carrier protein and utilizes ATP molecules. It transports the sodium ions to the extracellular space, increasing their concentration there and in turn moves potassium ions inside the cell. This pump moves three potassium ions inside the cell for every two sodium ions moved outside.


So, the correct answer is 'active transport'.

State whether the following statements are true or false.
ATP is required for active transport.

  1. True

  2. False


Correct Option: A
Explanation:

Active transport is usually associated with accumulating high concentrations of molecules that the cell needs such as ions, glucose, and amino acids. The processes use chemical energy for this, it comes from the hydrolysis of the ATP molecule which maintains the electrochemical gradient. Hence ATP is required for active transport. 

So, the correct option is 'True'.

State whether the following statements are true or false.
In the sodium-potassium pump, sodium is transported out of the cell and potassium is trapsported into the cell as ATP is broken by a membrane protein.

  1. True

  2. False


Correct Option: A
Explanation:

ATP acts as a solute pump, it's an enzyme that pumps out sodium and pumping potassium in the cells, exports three sodium, and two potassium ions. It is an active transport leading to the hydrolysis of ATP molecules to provide the required energy.

So correct answer is 'True'.

Which one of the following processes requires an input of energy?

  1. Active transport

  2. Diffusion

  3. Facilitated diffusion

  4. Osmosis


Correct Option: A
Explanation:

An input of energy is required in the process of active transport as it involves the movement of ions or molecules across a cell membrane from low to high concentration. The movement requires energy to maintain the electrochemical gradient.

So, the correct option is 'Active transport'.

State whether the following statements are true or false.
The movement of ions or molecules against a concentration gradient with the utilisation of energy is known as active transport.

  1. True

  2. False


Correct Option: A
Explanation:

The movement of ions or molecules against a concentration gradient (from lower to higher concentration) across a cell membrane with the utilization of energy is known as active transport. Active transport needs cellular energy which is given by ATP hydrolysis.

So, the correct option is 'True'.

Choose the correct answer from the alternatives given.
Which is the best definition of active transport?

  1. Movement of molecules from an area of their higher concentration to an area of their lower concentration

  2. Movement of water across a semi-permeable membrane from an area of high water concentration to an area of lower water concentration

  3. Movement of molecules from an area of their lower concentration to an area of their higher concentration

  4. Movement of a substance against its concentration through the release of energy from ATP


Correct Option: D
Explanation:
In one form of transport across the cell membrane, ATP is utilized. The utilization of an ATP molecule provides the cell with an energy boost which enables the transport of different molecules across the cell membrane against their concentration gradient. This is termed as active transport of molecules across the cell membrane.

So, the correct answer is 'Movement of a substance against its concentration through the release of energy from ATP'.
Which of the following is an energy-dependent process?
  1. Facilitated diffusion

  2. Active transport

  3. Endosmosis

  4. Exosmosis


Correct Option: B
Explanation:

Active transport is an energy dependent process, in which ATP is utilised.

Which of the following is an energy dependent process?

  1. Facilitated diffusion

  2. Active transport

  3. Endosmosis

  4. Exosmosis


Correct Option: B
Explanation:

Active transport (secretion) is an energy-dependent process that selectively moves a substance against its electrochemical gradient across a cell membrane. It is an energy dependent process, in which ATP is utilised.

Thus the correct option is B. 

Uphill transport i.e., movement of substances from their lower concentration to their higher concentration occurs in

  1. Simple diffusion

  2. Facilitated diffusion

  3. Active transport

  4. Both B and C


Correct Option: C
Explanation:

In active transport, the movable carrier proteins are called pumps. They employ ATP energy for transport across the membrane. It is uphill transport, i.e., against concentration gradient and is faster than passive transport. The rate of active transport reaches the maximum when all the protein pumps are being used in transport(saturation effect). Carrier proteins are highly specific like enzymes. They are also sensitive to inhibitors that react with protein side chains. So, the correct answer is 'Active transport'.

Channel proteins allow ions that would not normally pass through the cell membrane to go through the channel. What properties of the proteins are responsible for this? 

  1. The channels are often composed of charged or polar $R$ groups.

  2. The channels are often composed of hydrophobic $R$ group.

  3. $a$ and $b$

  4. None of these


Correct Option: A
Explanation:

Facilitated diffusion, therefore, allows polar and charged molecules, such as carbohydrates, amino acids, nucleosides, and ions, to cross the plasma membrane. Two classes of proteins that mediate facilitated diffusion are generally distinguished.

So, the correct option 'The channels are often composed of charged or polar R groups'.

The movement of ions against the concentration gradient is

  1. Active transport

  2. Osmosis

  3. Diffusion

  4. All of the above


Correct Option: A
Explanation:

Active transport is the movement of molecules across a cell membrane in the direction against their concentration gradient, i.e. moving from an area of lower concentration to an area of higher concentration. 

Osmotic theory for an active absorption of water was given by

  1. Thimann

  2. O. Hertwig

  3. Atkins and Priestley

  4. J. C. Bose


Correct Option: C
Explanation:

There are two methods of water absorption active and passive. Active water absorption requires energy. Osmotic active absorption theory was advanced first by Atkins in 1916 and later on by Priestley, 1921, for the maintenance of high salt content in xylem channels.

Carrier ions like Na$^+$ facilitate the absorption of substances like 

  1. Fructose and some amino acids

  2. Amino acids and glucose

  3. Glucose and fatty acids

  4. Fatty acids and glycerol


Correct Option: B
Explanation:

Absorption of glucose takes place with the help of a carrier protein that carries out the co-transport of glucose along with two sodium ions. Absorption of amino acids also takes place by a similar mechanism with the help of a sodium-dependent co-transporter. Absorption of fructose occurs by facilitated diffusion, and fatty acids and glycerol by a simple diffusion mechanism. 

So, the correct option is 'Amino acids and glucose'.

A student put five raisins each in two beakers A and B. Beaker A contained 50 ml of distilled water and beaker B had 50 ml of saturated sugar solution. After sometime, the student would observe that

  1. Raisins in beaker A were more swollen than those in beaker B.

  2. Raisins in beaker B were more swollen than those in beaker A.

  3. Raisins in both beaker A and B were equally swollen.

  4. Raisins in beaker A did not swell up at all.


Correct Option: A
Explanation:

Raisins in the beaker A will swell as solution surrounding them is hypotonic in nature. Hypotonic solution contains lesser solute concentration. In such case, endosmosis will occur in which inward movement of the water molecules from the lower solute concentration to higher solute concentration through raisin covering. 
Raisins in the beaker B will shrink 
as solution surrounding them is hypertonic in nature. Hypertonic solution contains higher solute concentration. In such case, exosmosis will occur in which outward movement of the water molecules from the lower solute concentration to higher solute concentration through raisin covering. 

Transporting pull arise mainly from

  1. Roots

  2. Leaves

  3. Stems

  4. All


Correct Option: B
Explanation:

As water is lost from the surface of the leaves due to transpiration a strong suction force is transmitted through the active mesophyll cells to the ends of the water column in the root. This is called transpiration pull. It caused the entire water column to be pulled upwards. When the rate of transpiration is very high and the rate of absorption is slow the water in the xylem elements of the leaf develops a state of tension.

So, the correct answer is B.

Which of the following does not operate in the carrier concept of active absorption of minerals?

  1. Electron transport

  2. Contractile protein

  3. Protein lecithin

  4. Ascending water stream


Correct Option: D
Explanation:
Plants absorb minerals from the soil in the form of inorganic ions. The process of mineral absorption and water absorption are separate processes occur in plants. Water absorption takes place actively by root pressure whereas mineral absorption takes place actively with the help of carrier proteins.
So the correct answer is 'Ascending water stream'.

Mineral absorption is mostly

  1. Physical process

  2. Chemical process

  3. Active process

  4. Passive process


Correct Option: C
Explanation:
Mineral absorption takes place in two phases: active absorption and passive absorption. It mostly occurs using active absorption phase because it is a fast process of mineral absorption, utilise energy and unidirectional. It is a biochemical process that occurs against the concentration gradient with the help of carriers and pumps.
So the correct answer is 'Active process'.

Which one is not connected with transport across the cell membrane?

  1. Osmosis

  2. Active transport

  3. Diffusion

  4. Surface tension


Correct Option: D
Explanation:

(A) Osmosis is the movement of the solute molecule from lower concentration to higher concentration through a semi-permeable membrane.

(B) Active transport is the transport of molecules which is energy dependent.
(C) Diffusion is the movement of molecules from a higher concentration to lower concentration.
(D) Surface Tension is the elastic tendency of a fluid surface to cover the least possible surface area.
So, the correct answer is 'Surface Tension'.

- Hide questions