Biology

Plant Transport and Physiology

2,012 Questions

Access a comprehensive set of questions on plant transport mechanisms and physiological adaptations. Topics include water movement, translocation of food, and plant responses to external stimuli. These biology questions are essential for medical entrance exams and other science competitive tests.

Xylem and phloem transportTranspiration and evaporationPlant adaptationsGeotropic and phototropic responsesWater absorption by rootsRespiration in roots

Plant Transport and Physiology Questions

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

Water enters from the soil into the root hairs due to

  1. Turgor pressure of root hair

  2. Osmotic pressure of root hair

  3. Suction pressure

  4. Diffusion pressure
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Suction pressure is same as DPD (Diffusion Pressure Deficit). Water moves in a plant due to suction pressure or DPD from a region of lower DPD to a region of higher DPD.

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

In a fully turgid cell, the values of DPD, OP and TP will show the tendency

  1. DPD$=$10atm, OP$=$15atm, TP$=$5atm
  2. DPD$=$5atm, OP$=$12atm, TP$=$7atm
  3. DPD$=$2atm, OP$=$7atm, TP$=$5atm
  4. DPD$=$0atm, OP$=$15atm, TP$=$15atm
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In a fully turgid cell there will be no net movement of water. Neither water will move inside nor move outside. This is because DPD will be zero. DPD can be zero, when the osmotic pressure, which causes movement of water inside the cell equals to turgor pressure, which opposes the entry of water inside the cell.

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

When the mesophyll cells lose water, their DPD will

  1. Increase

  2. Decrease

  3. Remain constant

  4. None of the above is applicable
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When the mesophyll cells lose water the concentration of solutes will increase. Consequently, the OP will increase concomitantly, there will be a drop in turgor and TP will decrease. These changes will increase the DPD. Water moves from lower DPD to higher DPD, thus, water will gain entry into the cells, whose DPD has increased.

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

In a plant cell the diffusion pressure deficit is zero when it is 

  1. Plasmolysed.

  2. Turgid.

  3. Flaccid.

  4. Incipient.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Diffusion Pressure Deficit = osmotic pressure - wall pressure. Wall pressure is the same as Turgor pressure. When a cell is placed in a hypotonic solution water enters the cell. Hence its osmotic pressure decreases and the turgor pressure increases. In a fully turgid cell the turgor pressure becomes equal to the osmotic pressure. Hence the Diffusion Pressure Deficit becomes zero in a turgid cell. Thus the correct answer is option B.

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

Root hair absorb water from soil due to

  1. Osmotic pressure

  2. Turgor pressure

  3. Suction pressure

  4. Root pressure
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Suction pressure is the decrease in the diffusion pressure of solution over its pure state due to the presence of solute particles in it. The concentration of solute is higher in root hair cells as compared to soil water. So suction pressure builds up and water is drawn towards root hair cells. These water molecules are transported to different parts of the plant. So, the correct answer is 'Suction pressure'.

Multiple choice botany plant water relation diffusion pressure deficit other pressure components osmosis in plants

DPD is abbreviated form of

  1. Daily photosynthetic deficit

  2. Daily phosphorus deficit

  3. Daily pressure deficit

  4. Diffusion pressure deficit
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Diffusion pressure deficit (DPD) is the amount by which two solutions differ in their diffusion pressure. The amount by which the diffusion pressure of water or solvent in a solution is lower than that of pure water or solvent is known as diffusion pressure deficit. It allows easy absorption of water due to diffusion pressure gradient. Water moves from lower DPD to higher DPD.
So, the correct answer is option D.
Multiple choice biology respiration in organism do plants breathe? plant respiration respiration-plants

Leaves of the plant have tiny pores for exchange of oxygen and carbon dioxide. These small pores are known as

  1. Nodule

  2. Stomata

  3. Radicle

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In plants, the stoma is a tiny opening found on the under-surface of leaves. These pores provide the passage for the entry of the air and the exchange of gases. They are also useful during transpiration for the escape of water vapour into the atmosphere.

So the correct option is 'Stomata'

Multiple choice biology respiration in organism do plants breathe? plant respiration respiration-plants

Plants take in .......... from the air and give out ..........

  1. Oxygen, Carbon dioxide

  2. Carbon dioxide, Oxygen

  3. Oxygen, Nitrogen

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Plants perform photosynthesis to obtain the light energy from direct sunlight and convert it into chemical energy. This process utilizes carbon dioxide, water and sunlight to produce carbohydrates and oxygen. It acts as a counterbalance to respiration by utilizing the carbon dioxide generated by all breathing organisms and giving out the oxygen back to the atmosphere. 

So the correct option is ' Carbon Dioxide, Oxygen'

Multiple choice chemistry water and air and their importance natural cycles and resources constituents of air component of air - nitrogen

Plants consumes ____________ and gives _____________.

  1. oxygen, carbon dioxide

  2. carbon dioxide, oxygen

  3. sulphur dioxide, oxygen

  4. oxygen, sulphur dioxide
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Plants consumes carbon dioxide and gives oxygen.

As in the process of photosynthesis plants consumes carbon dioxide and during photosynthesis plants release oxygen.

Multiple choice chemistry water and air and their importance natural cycles and resources constituents of air component of air - nitrogen

All the plants require nitrogen for:

  1. reproduction

  2. photosynthesis

  3. transpiration

  4. growth
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
All the plants require nitrogen for growth. Nitrogen is found in healthy soils and give plants the energy to grow and produce fruit or vegetables. Nitrogen is part of the chlorophyll molecule, which gives plant their green colour and is involved in  creating food for the plant through photosynthesis.
So, the correct answer is 'growth'
Multiple choice biology plant growth seed dormancy fruit plants: structure and function

A method of breaking dormancy and allowing ample absorption of water is

  1. Stratification

  2. Scarification

  3. Vernalisation

  4. Devernalisation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A. Stratification: Seeds are moistened and exposed to oxygen for variable period at low or high temperature.

B. Scarification: Hard, impermeable seed coat is weakened or ruptured by filing, chip­ping, abosrbing hot water.

C. Vernalisation- The cooling of seed during germination in order to accelerate flowering when it is planted.

D. Devernalisation- The heating of seed during germination in order to deaccelrating flowering when it is planted.
So, the correct answer is 'Scarification'.

Multiple choice biology mineral nutrition in plants hydroponics nutrients and nutrition hydroculture

When we boil tulsi leaves in water, water acquires a characteristic smell of leaves because

  1. Smell of leaves diffuse in water

  2. Leaves melt in water

  3. Stored wastes in the leaves dissolve in water

  4. Leaves pollute water
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Water acquires a characteristic smell because the smell of leaves diffuse in water, tulsi leaves never melt in water or pollute water.

So, the correct option is 'Smell of leaves diffuse in water'.

Multiple choice biology mineral nutrition in plants hydroponics nutrients and nutrition hydroculture

State whether the following statements are true or false.
Transfusion tissue is the substitute of lateral veins as it helps in the conduction of water.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Answer A: True
Transfusion tissue immediately surrounding at least part of the vascular bundles in the leaves of gymnosperms, e.g. Pinus. Transfusion tissue is composed of tracheids (transfusion tracheids) with conspicuous bordered pits , and parenchyma cells (transfusion parenchyma) containing tannin-like substances and sometimes starch. The main function of the transfusion tissue is believed to be the transport of materials between the vascular bundles and the mesophyll.