Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice transpiration major activities of living organisms biology

Prolonged liberal irrigation of agricultural fields is likely to create the problem of

  1. Acidity

  2. Aridity

  3. Metal toxicity

  4. Salinity
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Soil salinity is the salt content in the soil; the process of increasing the salt content is known as salinization. Salination can be caused by natural processes, such as mineral weathering or the gradual withdrawal of an ocean. It can also be caused by artificial processes such as irrigation. The ions responsible for salination are: Na$^{+}$, K$^{+}$, Ca$^{2+}$, Mg$^{2+}$ and Cl$^{-}$. When excess irrigation is done, the negatively charged ions are leached or washed away and only positively charged ions remain in the soil as they are held up by clay particles in the soil. This creates salinity problem.

Multiple choice transpiration major activities of living organisms biology

Collecters secreting sticky exudations are characteristic of

  1. Pyrus

  2. Rosa

  3. Nicotiana

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

In Botany, the term exudate refers to the fluid emitted through pores in the plants and the process is called as exuding. Examples of plant exudates are saps, gums, resins, latex and nectar. Sticky exudates are released from the glandular trichomes of the leaves or branches when damaged or even flowers. These sticky exudations are tactile signals of the plants which either work as alarm signals to the aphids, traps insects or are signals for pollinators.
Therefore, the correct answer is option D.

Multiple choice transpiration major activities of living organisms biology

Which of the following is not a function of transpiration?

  1. Uptake of water

  2. Evaporation of water

  3. Uptake of minerals

  4. Excretion of minerals
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Evaporation of water and uptake of minerals and water is a function of transpiration.

Transpiration causes water to take up the heat of the organs or the energy from sunlight and convert into water vapour causing evaporation of water.
Transpiration pull helps in ascent of xylem sap and hence helps in transportation of water and minerals.
Since water vapours are lost through transpiration, the minerals are left behind as they cannot evaporate along with water.
So the correct answer is 'Excretiom of minerals'.

Multiple choice transpiration major activities of living organisms biology

Transpiration is unavoidable evil because of

  1. Structure of leaf and harmful effect

  2. Beneficial and harmful effect

  3. Maintenance of turgidity for growth

  4. Gaseous exchange for photosynthesis and respiration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Stomata are the aperture which is mainly present at the dorsal surface of the leaf. It is meant for gaseous exchange but it also allows the loss of water through transpiration. Loss of water can lead to wilting, serious dessication and often the death of a plant if there is a shortage of water. 

Thus, the correct answer is an option D.

Multiple choice transpiration major activities of living organisms biology

A negative effect of transpiration is

  1. Development of water stress

  2. Increase in mineral absorption

  3. Maintenance of leaf temperature

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

Transpiration is the process of loss of water through the aerial parts of the plant. It depends upon the amount of humidity level of the atmosphere.

When there is a high level of moisture then there is no concentration gradient between leaf and the atmosphere there is a minimum loss of water through transpiration. It is a necessary evil as it develops water stress.
So, the correct answer is 'Development of water stress'.

Multiple choice transpiration major activities of living organisms biology

Soil pores with capillary water are

  1. Super pores

  2. Macropores

  3. Mesopores

  4. Micropores
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Water enters the soil through the pores by the means of capillary action and gravity. Microspores are soil pores with capillary water in it. They hold maximum water by capillary forces. These pores have high water holding capacity as water within these pores is immobile. However, water is readily available for plant.

Thus, the correct answer is option D.

Multiple choice transpiration major activities of living organisms biology

Chresard occurs in the soil

  1. Around soil particles

  2. Inside micropores

  3. Inside macropores

  4. In percolation chambers.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chresard is an available soil water to plants. Water enters the soil through the pores by the means of capillary action and gravity. Micropores hold maximum water by capillary forces. These pores have high water holding capacity as water within these pores is immobile. However, this water is available for plant. 

Thus, the correct answer is option B.

Multiple choice transpiration major activities of living organisms biology

Percolation of soil water to water table occurs through

  1. Micropores less than 0.2 $\mu $m
  2. Micropores between 0.2 to 20.0 $\mu $m
  3. Macropores between 20-50 $\mu $m
  4. Macropores bigger than 50 $\mu $m
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Infiltration is downward entry of water into the soil whereas percolation is the downward flow of water through soil. Percolated water reaches deep in the soil to water table. Percolation of water first occurs through macropores that are bigger than 50 micron. These are present between soil particles and microspores. Later, percolation occurs through microspores.

Thus, the correct answer is option D.

Multiple choice transpiration major activities of living organisms biology

Wetting of dried soil surface automatically during night without rain is

  1. Night recovery

  2. Dew wetting

  3. Mist formation

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

During night, the dried soil surface becomes wet. This is due to the water droplets that forms a thin layer due to condensation. This is called as night recovery. As the soil surface cools at night by radiating its heat, moisture present in the atmosphere condenses. This results in the formation of water droplets on the soil. At night as the air cools to the dew point, condensation occurs and soil becomes wet without rain.

Thus, the correct answer is option A.