Tag: botany

Questions Related to botany

Which of the following serves as indicator of atmospheric pollution? 

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Liverworts

  2. Hornworts

  3. Epiphytic lichens

  4. Ferns

Show answer
Correct Option: C
Explanation:

Lichens are the symbiotic association between the fungi and algae. They obtain almost all their nutrients from the atmosphere through uptake over their entire surface and thus called as epiphytic lichens. They have no cuticle, nor means of controlling nutrient uptake, unlike vascular plants, and free exchange of both gasses and solutions occurs across cell surfaces. Lichens are therefore highly susceptible to changes in atmospheric composition and for this reason provide very sensitive indicators of such changes. Lichens are sensitive to sulphur, nitrogen, acidity, halogens (e.g., fluoride), heavy metals and ozone.

Therefore, the correct answer is option C.

Lichens are important in the studies on atmospheric pollution because they

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Can also grow in greatly polluted atmosphere

  2. Can readily multiply in polluted atmosphere

  3. Are very sensitive to pollutants such as $SO _2$

  4. Efficiently purify the atmosphere

Show answer
Correct Option: C
Explanation:

Lichens are used as the indicators of air pollution. These structures grow on tree bark and rocks. Air pollutants which are in the gaseous forms get dissolved in the rainwater, especially pollutants like SO$ _2$ can damage lichens, and check them from growing. In places where lichens are not growing, it indicates that the air is heavily polluted with sulphur dioxide and other pollutants. 

Thus, the correct answer is option C. 

In a highly industrialised area, which of the following will be virtually absent?

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Algae

  2. Lichens

  3. Ferns

  4. Bryophytes

Show answer
Correct Option: B
Explanation:

In a highly industrialized area, lichens will be virtually absent as these area will be highly polluted and lichens are useful bioindicators for air and water pollution specially for sulphur dioxide pollution. Their efficient absorption systems results in rapid accumulation of sulphur when exposed to high levels of sulphur dioxide pollution and the algal partner are most affected by the sulphur dioxide as chlorophyll is destroyed and photosynthesis is inhibited.

So, the correct answer is option B.

In organisms like lichens, the number of partners are

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Three

  2. Two

  3. Four

  4. Six

Show answer
Correct Option: B
Explanation:

Lichens have a symbiotic relationship. In this type of relationship, lichens live symbiotically. there is a symbiotic relationship between algae and fungi in lichens. Algae perform photosynthesis and provide with carbon compounds. Fungi provide protection and nutrition to algae. Thus, 2 organisms are involved in a lichen. 

So, option B " Two" is the correct answer.

Lichen is usually cited as an example of symbiosis in plants where an algal and fungal species live together for their mutual benefit. Which of the following will happen if algal and fungal partners are separated from each other in laboratory conditions?

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Both will survive and grow normally and independent from each other.

  2. Both will die.

  3. Algal component will survive while the fungal component will die.

  4. Fungal component will survive while the algal component will die.

Show answer
Correct Option: C
Explanation:

Algae are green photosynthetic organisms. They are autotropic as they perform the process of photosynthesis to prepare their own food. Lichens cannot prepare their own as they are non-photosynthetic. So, inn absence of lichens , algae can survive as they can prepare their own food. But lichens will starve and ultimately die. 

So, option C is the correct answer.

Which of the following is the use of lichens in case of pollution?

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. They treat the polluted water

  2. They act as bioindicators of pollution

  3. They promote pollution

  4. Lichens are not related with pollution

Show answer
Correct Option: B
Explanation:
Bioindicators are living organisms that respond in an especially clear way to a change in the environment. The hardy lichens are useful bioindicators for air pollution, especially sulfur dioxide pollution, since they derive their water and essential nutrients mainly from the atmosphere rather than from the soil. It also helps that, they are able to react to air pollutants all year round. Compared with most physical/chemical monitors, they are inexpensive to use in evaluating air pollution.
Lichens can also be used to measure toxic elemental pollutants and radioactive metals because they bind these substances in their fungal threads where they concentrate them over time. Environmental scientists can then evaluate this accumulation to determine the history of the local air
So, the correct answer is 'They act as bioindicators of pollution'

Biological weathering of rock is caused by 

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Lichens

  2. Mosses

  3. Roots of plants

  4. All of the above

Show answer
Correct Option: D
Explanation:
  • The weathering of rocks is responsible for the formation of soil. It occurs due to a variety of reasons like under the effect of lichens. 
  • Lichens cause the breakdown of rock materials and organic minerals. Thus they breakdown the surface of rocks.
  • Mosses also release different gases and cause the breakdown of rocks they grow on.
  • Roots of plants that grow on rocks cause cracks on the surface of rocks.
  • Thus, all these factors are responsible for the weathering of rocks.

Which among the following is a good source of a natural dye of litmus? 

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Algae

  2. Fungi

  3. Lichen

  4. Mosses

Show answer
Correct Option: C
Explanation:

The species of the lichen Rocella is used for the extraction of the dye which serves in the formation of litmus. The litmus papers are used for testing of the pH. The litmus paper turns blue at alkaline pH and red at acidic pH. The change in the pH can be analysed using the litmus papers. 

Thus, the correct answer is option C. 

Which of the following is lichen?

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Apple moss

  2. Peat moss

  3. Reindeer moss

  4. Club moss

Show answer
Correct Option: C
Explanation:

Reindeer moss is a type of lichen. It grows in arctic regions and is a bluish-grey organism. In winters, it provides food for reindeer. Apple moss, peat moss and club moss are typical mosses. 

So, option C " Reindeer moss" is the correct answer.

Lichens show the symbiotic association between

botany adaptations to different ecosystems lichen lichens lichens ( the nature's pioneers )

  1. Algae and fungi

  2. Fungi and bacteria

  3. Bacteria and virus

  4. Fungi and roots of higher plants

Show answer
Correct Option: A
Explanation:
A lichen is a stable symbiotic association between a fungus and algae and/or cyanobacteria. The lichen symbiosis is thought to be a mutualism, as both the fungi and the photosynthetic partners, called as photobionts, benefit. The algal component photosynthesize and provide food for the fungus while the fungal component provide protection from the environment by its filament.
Thus, the correct answer is option A.