Transport in Plants Test - 38

Solution

Correct answer is option C.

• Explanation for correct option:
• Transpiration is evaporation of excess water from plants through its aerial parts like stem , leaves, flower.
• Depending upon the plant surface transpiration is of  3 main types- Stomatal Transpiration, Cuticular Transpiration, Lenticular Transpiration.
• This process is famously called Necessary evil in plants  because although it causes loss of water, it maintains the temperature of plant , makes them cool. 

Solution

Correct answer is option B.

Explanation for correct option:

• The given figure is of phloem tissue.
• Here P are sieve tubes, Q represents companion cell, R is phloem, S depicts sieve plate.
• The companion cell is the cell responsible for the metabolic life of the sieve elements, including the transport of carbohydrates in and out the sieve elements.
• Companion cells also help in maintaining a proper pressure gradient in the sieve tube elements.

Solution

Correct answer is option A.

Explanation for correct option:

• Phloem is composed of sieve tubes, companion cells, phloem fibres and the phloem parenchyma. Its function is transport of food from leaves to other plant parts.
• Transport of soluble product of photosynthesis or food from leaves to other parts of plants is called translocation.
• For translocation, food molecules enter the part of the phloem called the sieve tubes where they can be transported upwards or downwards to all the parts of the plant including roots.