Tag: botany

Quizzes (264) Questions (5276)

Questions Related to botany

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Which of the following force accounts for the ascent of sap?

  1. Adhesive force

  2. Cohesive force

  3. Transpirational pull

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The ascent of sap is the mechanism by which water moves from the roots to the top of the trees. Studies on the process of an ascent of sap show that the strong cohesive force between the water molecules (cohesion), the attraction between water molecules and the wall of the xylem elements (adhesion) and the transpiration pull creates a tension on the water column, which ensures continuity of water column in plants. The water lost from the leaves during transpiration creates a high solute potential and reduces water potential. The reduced water potential creates a suction pull and allows ascent of sap. 

Thus, the correct answer is option D.

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Which of the following theory gave the most satisfactory explanation for the ascent of sap?

  1. Relay pump theory

  2. Transpirational pull theory

  3. Root pressure theory

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

The transpiration pull theory is the most accepted theory for the ascent of sap. Dixon and Jolly gave transpiration pull theory. According to this theory, the ascent of sap in plants is a passive physical process, which occurs under the influence of transpiration pull generated due to loss of water from aerial parts. The water lost from the leaves creates a high solute potential and reduces water potential. The reduced water potential creates a suction pull and allows ascent of sap. Other than the pull, a continuous column of water is also essential for the rise of water in xylem elements. The continuous column of water is maintained by cohesion forces between water molecules and adhesive forces between water molecules and vascular elements of the plant.

Thus, the correct answer is option B. 

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

J.C.Bose supported 

  1. The ascent of sap takes place due to cohesive force.

  2. The ascent of sap takes place due to adhesive force.

  3. The ascent of sap takes place due to pulsatory activity of living cell.

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

The movement of water in the plants is known as the ascent of the sap. This upward movement is due to the pulsatory activity of the living cell. This theory was supported by J. C. Bose. he explained that there is rhythmic form of pulse-like movement which helps the water to be transported in the upward direction. 

Thus, the correct answer is option C. 

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Which of the following statements was supported by Westermaier?

  1. The upward conduction of water is provided by cohesive force.

  2. The upward conduction of water is provided by xylem parenchyma cells.

  3. The upward conduction of water is provided by pulsatory action of living cells.

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

There are several vital theories which help in understanding the concept of the conduction of water by xylem. Westermaier explained the theory that the upward conduction of water is due to xylem parenchyma cells. The tracheids and the vessels act as water reservoirs. This allows the movement of the water in upward direction. 

Thus, the correct answer is option B. 

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Which part helps the plant absorb water and mineral from the soil?

  1. Root hairs

  2. Roots

  3. Root cap

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

Tap root is a type of roots which has a major big central root and small branching. These go very deep in the soil and are very strong.

Root cap helps the root to grow in length by cell division.
Roots are the general organs of the plants that absorb water but more specifically it is the root hair present on the root that significantly increase the surface area available for absorption of water and minerals.
So, the correct answer is 'Root hairs'.

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Water in plants is transported by or ascent of sap takes place through 

  1. Cambium

  2. Phloem

  3. Xylem

  4. Epidermis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Xylem contributes in ascent of sap by the following phenomena.
1) The rate of transpiration is high. 
2) The water is lost from guard cell which leads to decrease in the water potential of guard cell as compared to the surrounding cell. 
3) To stabilize the water potential in the guard cell water rushes from the neighbouring cell which creates a cohesion pull in the xylem vessels to pull the water up to the guard cell. 
So, the correct answer is option C.
Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

Ascent of sap is

  1. Upward movement of water in the plant.

  2. Downward movement of organic nutrients.

  3. Downward and upward movement of water in the plant.

  4. Redistribution of inorganic substances in the plant.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • Down to upwards movement is known as ascent and Top to downwards movement is known as descend.
  • In plants sap is water and minerals.
  • Ascent of sap in the xylem tissue of plants is the upward movement of water and minerals from the root to the top. 
Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

The gridling or ringing experiment to prove that the water moves through the xylem vessels was performed by

  1. Stocking

  2. Malpighi

  3. Molisch

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

This experiment was introduced by Malpighi in 1675. It involves the removal of a ring of bark (girdle), that is, all tissues outside the vascular cambium. Thus, the correct answer is (B).

Multiple choice botany water absorption and ascent of sap in plants apoplast and symplastic pathway transport of water in plants water transport

The transport of sap from root to top of the plant is

  1. Ascent of sap

  2. Conduction

  3. Transport

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

When any material movement is from down to upwards it is called as ascending movement.

When material movement is from top to downwards it is called as descending movement.
The upward movement of water and minerals from the root to the top of the plant is called as ascent of sap. Plants absorb water through the root hairs and transpire through leaves. The water moves from the root to the tip portion of the plant body against the force of gravity by transpiration pull.