Competitive Exams: Botany MCQs (Practice-Test 81 of 104)

  1. 6p23 in chromosome nomenclature indicates band number

    1. 6 in short arm of chromosome 23

    2. 3 in region 2 of short arm of chromosome 6

    3. 3 in region 2 of long arm of chromosome 6

    4. 6 in long arm of chromosome 23

  2. Crossing over occurs between

    1. Homologues chromosomes

    2. Sister chromatids

    3. Chromatids of homologous chromosomes

    4. Any to chromosomes

  3. There are some chemicals which are structurally similar to the base normally found in DNA, and can be incorporated in place of a normal base. One such base analogue is

    1. 5-bromouracil

    2. Nitrous acid

    3. Ethyl methane sulphonate

    4. Methyl methane sulphonate

  4. In aqueous solution, the alcidine molecules bind to DNA by inserting themselves between adjacent base pairs. The process is called

    1. Depreciation

    2. Substitution

    3. Muation

    4. Intercalation

  5. Match List I (Type of chromosomal aberration) with List II (Designation) and select the correct answer using the codes given below the lists:

    List-I List-II
    1. One chromosome pair extra to the normal complement (2n + 2)

    2. One chromosome extra to the normal complement (2n + 1)

    3. One chromosome less than the normal complement (2n − 1)

    4. One chromosome pair less than the normal complement (2n − 2)

    1. Trisomic

    2. Monosomic

    3. Terasomic

    4. Nullisomic

    • A
    • B
    • C
    • D
      • 2
      • 4
      • 3
      • 1
      • 1
      • 3
      • 2
      • 4
      • 3
      • 1
      • 4
      • 2
      • 3
      • 1
      • 2
      • 4
  6. Match List I (Discovery) with List II (Scientist) and select the correct answer using the codes given below the lists:

    List-I List-II
    1. Breaking of the genetic code

    2. Synthesis of an artificial gene

    3. DNA/DNA and DNA/RNA hybridization in situ

    4. Phenomenon of transduction

    1. Pardue and gall

    2. Zinder and Lederberg

    3. Nirenberg and Matthaei

    4. Khorana

    • A
    • B
    • C
    • D
      • 1
      • 2
      • 3
      • 4
      • 2
      • 4
      • 3
      • 1
      • 3
      • 4
      • 1
      • 2
      • 1
      • 3
      • 2
      • 4
  7. When Mendelian principles are operative during the distribution of the alleles into gametes, such a phenomenon is referred to as

    1. Potential function of an allele

    2. Co dominance

    3. Gene interaction

    4. Continuous variation

  8. A vector specifically designed for cloning 40 − 49 kb DNA fragment is

    1. Plasmid

    2. Phagmid

    3. Cosmid

    4. BAC

  9. In which one of the following plant species can self-pollination never occur either naturally or artificially?

    1. Zen mays

    2. Gossypium hirsutum

    3. Saccharum officinarum

    4. Carica papaya

  10. The Hardy-Weinberg law is expressed as (p + q) 2, where p and q stands for

    1. Frequency of heterozygote

    2. Frequency of alleles in population

    3. Gene frequencies in population

    4. Genotypes frequencies in population

  11. Mendel had no idea about

    1. Independent assortment

    2. Segregation of alleles

    3. Dominance and recessive ness

    4. Linkage

  12. Which one of the following viruses has single stranded DNA and is used extensively as cloning vector in recombinant DNA technology?

    1. TMV

    2. lambda phage

    3. Adenovirus

    4. M13

  13. Mobile genetic elements in maize were discovered by

    1. D. Baltimore

    2. H. G. Khorana

    3. N. E. Borlaug

    4. B. McClintock

  14. Norine-10 is

    1. Retrovirus causing enteritis

    2. Dwarfing gene in wheat

    3. Wheat variety resistant to black rust

    4. Fungicide

  15. The polypeptide chain initiation in a prokaryotic cell, always begins with the amino acid f-methionine because

    1. No peptide bond formation can take place at the amino end of f-methionine as it is formulated

    2. F-methionine is available in abundance in the bacterium

    3. F-methionine can help chain elongation

    4. Only one t-RNA can attach with fmethionine