Competitive Exams: Botany MCQs (Practice-Test 62 of 104)

  1. In the given graph, the arrow indicates specifically

    1. Biotic potential

    2. Density-dependent effect

    3. Density-independent effect

    4. Carrying capacity

  2. Secondary plant succession can occur after

    1. Farmland is cultivated

    2. Forests have been burned

    3. Bare rock is exposed from a retreating glacier

    4. Sand dunes are created

  3. Which one of the following statements in correct?

    1. Up to about 15 km above the Earth's surface, ozone is beneficial to life but chlorofluorocarbons are harmful

    2. Beyond about 20 km above the Earth's surface, preserce of ozone is vital to life on Earth and chlorofluorocarbons are beneficial

    3. Beyond about 20 km above the surface of the Earth, ozone is vital to life on Earth, but chlorofluorocarbons are harmful

    4. Up to about 15 km above the Earth surface both ozone and chlorofluorocarbons are harmful to life

  4. Consider the following species:

    1. Borassus flabelliform

    2. Elaeis guineensis

    3. Oreodoxa regia

    4. Phoenix sylvestris

    Palm oil is obtained from

    1. 1 and 2

    2. 2 and 4

    3. 2 alone

    4. 4 alone

    • Assertion (A): The cells possessing potential to undergo cell division can be easily identified under the microscop.
    • Reason (R): The merisematic cells contain prominent nuclei and denser cytoplasm
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Ginkgo balboa is a living fossi.
    • Reason (R): Today, it exists on the Earth as a surviving type of ancient primitive seed plant
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): The wood of Finns provides commercially important timbe.
    • Reason (R): The wood of Pinus is monocyclic
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Housewives keep cut potato pieces submerged in water if not required for immediate use for cookin.
    • Reason (R): This helps in softening the potato pieces
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): A farmer does not prefer to grow tobacco plant under long day condition.
    • Reason (R): Tobacco is a short day plant
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): If a graminaceous seedling is exposed to light, it would bend towards ligh.
    • Reason (R): The curvature of seedling is caused by asymmetric distribution of hormone induced by light
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Saprogenic parasitic a is parasitic on fis.
    • Reason (R): All species of Saprogenic are parasitic on fish
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Cryopereservation is one of the best methods of germplasm storag.
    • Reason (R): In cry preservation, the cells remain in a state of suspended animation
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

    • Assertion (A): Seed and plant samples of only genetically superior and cultivated species are introduced from one country to anothe.
    • Reason (R): The cultivated species find a direct use in the crop improvement programmes of the importing country
    1. Both A and R are true and R is the correct explanation of A

    2. Both A and R are true but R is not a correct explanation of A

    3. A is true but R is false

    4. A is false but R is true

  5. The concept about the origin of life has changed in the recent past and it is now believed that it was an RNA world which led to the origin of life. This belief is based on the discovery that RNA

    1. Can be used for the synthesis of DNA, using the reverse transcriptase enzyme

    2. Can work as an enzyme

    3. Is used as mrna, trna and rrna during protein synthesis

    4. Is used as a genetic material in some viruses

  6. Two unrelated organisms that become similar in appearance and ways of life as they adapt to similar environmental situations exhibit

    1. Adaptive radiation

    2. Convergent evolution

    3. Parallel evolution

    4. Homology