NET, IAS, State-SET (KSET, WBSET, MPSET, etc.), GATE, CUET, Olympiads etc.: Botany MCQs (Practice_Test 96 of 104)

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  1. Consider the following statements regarding the introduction of plant materials and seeds.
    1. Plant materials and seeds are always introduced from developed countries into developing⟋less developed countries.
    2. The import of living plant materials must be accompanied by a certificate of health to prevent introduction of new diseases and insect pests.
    3. The superior varieties may be used in hybridization programmes.
    • Of these statements
      1. 1,2 and 3 are correct
      2. 1, and 2 are correct
      3. 2 and 3 are correct
      4. 1 and 3 are correct
    • Assertion (A) : Energy required for the formation of a soup of organic molecules and later complex molecules acquiring characteristics of life in water was obtained from uv rays of the sun, radioactivity, electric discharges etc.
    • Reason (R) : Life originated in water possibly in the form of bacteria.
      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 presence of tyloses prevents rapid entrance of water, air and fungal filament.
    • Reason (R) : Tyloses are formed by the enlargement of the pit membrane of the half-bordered pit-pairs between wood parenchyma and tracheids.
      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 cyan bacterium Anabaena is a diazotroph.
    • Reason (R) : Heterocyst of Anabaena lack photo system II.
      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 large number of amino acids are not incorporated in proteins and are highly toxic.
    • Reason (R) : The ‘non-protein’ amino acids provide chemical defense to plants and have been exploited for taxonomic studies.
      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) : 14C is widely used in biological studies for tracing metabolic pathways.
    • Reason (R) : 14C is the only isotope of carbon which bines with he bimolecular.
      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) : Xanthium will not flower if the long dark period is interrupted by a single brief flash of light.
    • Reason (R) : Xanthium is a short day plant where continuous long dark period is essential for flowering.
      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) : Asexual reproduction is of great advantage to the plant improvement programme of a particular species.
    • Reason (R) : An indefinitely large number of genetically identical individuals can be obtained irrespective of the degree of heterozygosis of the genotype.
      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) : Entomophilies plants produce less pollen when compared to anemophilous plants.
    • Reason (R) : The wastage of pollen is reduced to the minimum in entomophilies plants because of the directional pollination.
      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) : Meiosis results in the formation of gametes with altered combination of genes.
    • Reason (R) : The segregation of genes taken place during the formation of gametes.
      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 transonic plant exhibits a quadrivalent configuration at metaphase I.
    • Reason (R) : It may be a frisomic with two Tran located chromosomes which results in the manifestation of quadrivalent configuration at metaphase-I.
      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) : In eukaryotic plants, the sequence of m RNA of a given gene is different from the sequence present in the genomic DNA.
    • Reason (R) : The eukaryotic genes have non-coding intron sequences which are spliced during mRNA processing.
      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) : It has been noticed that when a plant is infected by agro bacterium tumefactions the (causal organism of crown gall) , some galls lack bacterial cells.
    • Reason (R) : In galls lacking bacterial cells, the TIP (tumors inducing principle) is carried in a large circular extra chromosomal DNA element.
      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) : Mangroves are typical halophyte.
    • Reason (R) : They flourish in sandy soil that is not very saline.
      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) : Social forestry needs approaches and attitudes that are quite different from what are needed for conventional forestry.
    • Reason (R) : Social forestry is production based and consumption oriented whereas conventional forestry is protection based and revenue oriented.
      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