Tag: major activities of living organisms

Quizzes (79) Questions (35)

Questions Related to major activities of living organisms

Multiple choice transpiration major activities of living organisms biology

The chief role of transpiration in plants is to cause

  1. Loss of surplus water

  2. Cooling of the plant

  3. Rapid ascent of sap

  4. Rapid rise of minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation


Transpiration is the process by which plants throw out the extra water present in it. Since water is an essential ingredient in the survival of the plants, it is absorbed through the roots. However, only a small amount of water is taken up for the metabolic activity. The rest 90-95% water is thrown out through the process of transpiration. The stomata along with the guard cells present in the underside of the leaves help the plants to transpire.  The process of transpiration enables the mass flow of mineral and water from the roots to the shoots and thus maintains the osmotic pressure of the cells and cools the plants.

Multiple choice transpiration major activities of living organisms biology

Day time loss of water in the vapour form from stomata is a trade off for intake of 

  1. Minerals

  2. Oxygen

  3. Carbon dioxide

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

In the day-time, when photosynthesis occurs, the guard cells are turgid while in the evening, regardless of the availability of water, these guard cells lose turgidity. When they are turgid, stomata open, and carbon dioxide enters freely. When they are flaccid, carbon dioxide is largely excluded, but water loss is also retarded. hence, the daytime loss of water in the vapor form from stomata is a trade-off for intake of carbon dioxide.

Thus, the correct answer is option (C). 

Multiple choice transpiration major activities of living organisms biology

In water-logged soil, plants do not grow properly because _______________.

  1. The soil is physiologically dry

  2. The soil is physiologically wet

  3. Due to excessive water

  4. Due to shortage of water
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In water-logged soil, air is displaced by water. Roots cannot respire aerobically, leading to a lack of energy for active water absorption, making the soil physiologically dry for the plant.

Multiple choice transpiration major activities of living organisms biology

Which of the following will not make minerals more available to plants?

  1. Increasing the rainfall in a wet forested area.

  2. Raising the pH of a very acidic soil.

  3. Tillering a packed-down or water-logged soil.

  4. Introducing fungi that can form mycorrhiza into a soil that lacks them.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Increased rainfall will lead to washing away of mineral elements along water, hence, it will not make minerals more available to plants.

Multiple choice transpiration major activities of living organisms biology

Which of the following is not the purpose of transpiration process?

  1. Supplying water for photosynthesis

  2. Maintaining shape and structure of plants

  3. Translocation of sucrose from source to sink

  4. Cooling the leaf surfaces
Reveal answer Fill a bubble to check yourself
C 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. 
So, the correct answer is 'Translocation of sucrose from source to sink'.

Multiple choice transpiration major activities of living organisms biology

Which of these is not the goal of transpiration?

  1. Prevention of loss of water

  2. Helping in the absorption and transportation process

  3. Supplying water for photosynthesis

  4. Keeping the plant cool
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Transpiration helps in the absorption of carbon dioxide gas from the atmosphere and its transportation.

It also helps in maintaining the temperature of the plant by releasing water which gets evaporated taking away the heat of the plant.
Transpiration leads to water loss so it cannot prevent loss of water.
So the correct answer is 'Prevention of loss of water'.

Multiple choice transpiration major activities of living organisms biology

Maximum water loss occurs through

  1. Lenticles

  2. Hydathodes

  3. Stomata

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

Water is essential for plants, it absorbs water from the soil through roots. However, plants absorbs much water, but only a small amount of water is used for their growth and metabolism. Persisting 97 - 99.5% of absorbed water is lost by transpiration. Transpiration is the process of elimination water in the form of water vapour from the aerial parts such as leaves, flowers and stem. The leaves contains tiny pores called stoma which helps in the gas exchange of oxygen and carbon dioxide. More the stoma (pores) on the leaves result in the increase in the transpiration via stomata. The leaf with the bigger surface area will transpire more when compared to the lower surface area. Each stomata is gaurded by guard cells which helps in the opening and closing of stomata. When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease.

So, the correct answer is option C.

Multiple choice transpiration major activities of living organisms biology

In hot summer day, plant cooling occurs due to

  1. Transport of water from root to all parts of the plants.

  2. Loss of liquid water

  3. Water loss from entire plant

  4. Loss of water vapour from foliar surface
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In hot summer days when loss of water vapour occurs from foliar surface because these are the main site of water loss or transpiration and directly exposed to sunlight.

There is no effect on cooling of plants due to transport of water from root to all parts of the plant or water loss from entire plant.

Multiple choice transpiration major activities of living organisms biology

Plant cooling occurs due to 

  1. Assimilation

  2. Guttation

  3. Photorespiration

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

Transpiration is the evaporation of the water from the stomata of the plants. The water absorbed by the roots is transported up to the leaves where stomata are present. Stomata open during the daytime and increasing temperature results in loss of water in the form of vapours. This is similar to the sweating process that occurs in humans. It cools the plants during high temperature.

Assimilation is the use of minerals by plants.
Guttation is oozing out of water in liquid form during night-time.
Photorespiration is a deviation in photosynthesis when the concentration of oxygen increases.
Transpiration is evaporation of water due to increased temperature during daytime.
So, the correct answer is 'Transpiration'.

Multiple choice transpiration major activities of living organisms biology

Water lost through transpiration is 

  1. Pure water

  2. Rich in organic solutes

  3. Rich in dissolved salts

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

Transpiration is the process of the evaporation of water molecule from the upper surface of the leaves.

The water eluted out is the water without any solute concentration, so the water is pure.
So, the correct answer is 'Pure water'.