Biology

Plant Transport and Physiology

1,834 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

Root pressure does not occur in

  1. gymnosperms.

  2. angiosperms.

  3. monocots.

  4. dicots.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Root pressure is maintained due to xylem vessels. Gymnosperms lack vessels, thus do not possess root pressure.

Multiple choice

Match the following:

 
a. The process of releasing surplus water into the air by plants 1. Evaporation
b. The process of changing of water into vapours 2. Water cycle
c. The process of changing of water vapours into water 3. Transpiration
d. The process of transfer of water from oceans to atmosphere and back to oceans 4. Condensation

  1. a – 3, b – 1, c – 4, d – 2

  2. a – 3, b – 1, c – 2, d – 4

  3. a – 1, b – 3, c – 4, d – 2

  4. a – 2, b – 1, c – 4, d – 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The process of releasing surplus water into the air by plants is called transpiration. The process of changing of water into its vapours is called evaporation, while changing of water vapours into water is called condensation. The journey of water from oceans to atmosphere and back to oceans is called water cycle.

Multiple choice

Match the following ||| |---|---| |a. Condensation|1. It is the process through which the plants release the surplus water into the air through their leaves.| |b. Precipitation|2. It is the falling of water drops from the clouds.| |c. Transpiration|3. It is the change of gaseous form of water into the liquid state on cooling.|

  1. a – 3, b – 2, c – 1

  2. a – 3, b – 1, c – 2

  3. a – 2, b – 3, c – 1

  4. a – 1, b – 2, c – 3

  5. a – 1, b – 3, c – 2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct option. Condensation is the change of gaseous form of water into the liquid state on cooling. Precipitation is the falling of water drops from the clouds. Transpiration is the process through which the plants release the surplus water into the air through their leaves.

Multiple choice

Which of the following structures does not help in the gaseous exchange in plants?

  1. Stomata

  2. Lenticels

  3. Petiole

  4. General Surface of the Roots

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A petiole is the stalk or stem that connects the leaf to the plant It is usually attached to the shoot at the node, subtending (attached beneath) the lateral meristem (axillary bud). On a compound leaf, the petiole extends from the stem to the first set of leaflets.It does not helps in the gaseous exchange 

Multiple choice

More dew is formed on grass than on a metallic utensil because

  1. there is transpiration in plants

  2. grass attracts dew drops on account of photosynthesis

  3. grass being good radiator, enables water vapour in the air to condense on it

  4. grass is a good conductor
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Grass is a good radiator of heat, meaning it loses heat quickly at night. This causes its temperature to drop below the dew point of the surrounding air, leading to condensation, whereas metals are generally poor radiators.

Multiple choice

During guttation, water is lost from

  1. stomata

  2. lenticels

  3. hydathodes

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

Guttation is the exudation of drops of xylem sap on the tips or edges of leaves through specialized pores called hydathodes.

Multiple choice

The cause of permanent wilting is

  1. rapid translocation

  2. rapid transpiration

  3. poor availability of soil water

  4. deficiency of nutrients
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Permanent wilting occurs when the soil water content drops to a level where the plant can no longer extract enough water to maintain turgor pressure. This is directly caused by the poor availability of water in the soil, even if the plant is physiologically healthy.

Multiple choice

Wilting of the plant occurs when

  1. xylem is blocked

  2. phloem is blocked

  3. both xylem and phloem are blocked

  4. a few roots are removed
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Xylem tissue is involved in water conducting system of plants; so if it is blocked, the plant will show wilting. The process of wilting modifies the leaf angle distribution of the plant (or canopy) towards more erectophile conditions.

Multiple choice

Maximum transpiration occurs from

  1. dermal tissue

  2. ground tissues of scale leave

  3. periderm and lenticels

  4. protoderm and procambium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Most transpiration occurs through the stomata located in the epidermis (dermal tissue) of leaves.