Transpiration_MCQ_Basic Level

Transpiration - Basic

Dear Readers,

Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers. Water is necessary for plants but only a small amount of water taken up by the roots is used for growth and metabolism. The remaining 97–99.5% is lost by transpiration and guttation

Q1. Which of the following would increase the rate of transpiration from the leaves of a potted plant ?

•  Put it in the dark for twenty four hours
•  Put it in the drought of an electric fan
•  Put it in a cold room
•  Put it outside when it is raining

Put it in the drought of an electric fan

Q2.  Which one of the following describes a possible reason for the opening and closing of the guard cells ?

•  Stomata open in daylight because photosynthesis occurs in the guard cells producing sugar resulting in higher osmotic pressure
•  Stomata open in daylight because guard cells have chloroplasts and the epidermal cells do not, and so a differential osmotic pressure arises
•  Stomata open in daylight because starch is changed to osmotically active substances which increase the turgidity of the guard cells
•  Stomata close in darkness because the starch produced in daylight by photosynthesis, it is changed into sugars and translocated from the guard cells

Stomata open in daylight because starch is changed to osmotically active substances which increase the turgidity of the guard cells

Q3. Which one of the following would lead to stomatal closure ?

•  Decrease in carbon dioxide concentration in the intercellular spaces of the leaf
•  Active photosynthesis in the stomatal guard cells
•  Conversion of sugar to starch in the stomatal guard cells
•  Increase in pH in the stomatal guard cells

Conversion of sugar to starch in the stomatal guard cells

Q4.  In Vallisneria, stomata are

•  Present on upper epidermis of leaf
•  Present on lower epidermis of leaf
•  Present on both the epidermis of leaf
•  Not present

Not present

Q5.  In the mechanism of opening of stomata, the important factor is the

•  Shape of the guard cells
•  Chlorophyll content of the cells
•  Hormone content of the cells
•  Protein content of the cells

Shape of the guard cells

Q6. Generally stomata found on the lower surface of leaf. Thus approximate percentage of transpiration through abaxial surface is

•   47%
•  57%
•  67%
•  97%

97%

Q7.  In walnut, stomata are found on

•  Only upper surface of the leaf
•  Only lower surface of the leaf
•  Both the surfaces of the leaf
•  Absent on both the surfaces

Only lower surface of the leaf

Q8.  In pea plant, type of stomata is known as

•  Apple type
•  Potato type
•  Oat type
•  None of these

Potato type

Q9.  Stomata is absent in

•  Submerged plants
•  Desert plants
•  Floating plants
•  All the above

Submerged plants

Q10.  Stomata closed and open due to activity of water then movement is known as

•  Photoactive
•  Scotoactive
•  Hydroactive
•  Autonomous

Hydroactive