Competitive Exams: Botany MCQs (Practice-Test 53 of 104)

  1. A ratio of the observed frequency of double-crossovers to the expected frequency of double-crossovers is known as which one of the following?

    1. Coefficient of selection

    2. Coefficient of coincidence

    3. Coefficient of variation

    4. Coefficient of inbreeding

  2. Genes that exhibit criss-cross inheritance are

    1. Dominant genes

    2. Co dominant genes

    3. Sex-linked genes

    4. Sex-limited genes

  3. Which of the following DNA sequences are located upstream of transcription initiation sites in E. Coli?

    1. Hogness box

    2. Pribnow box

    3. CAAT box

    4. MADS box

  4. The factors responsible for cytoplasm male sterility are located in the

    1. Chloroplast DNA

    2. rRNA

    3. Nuclear DNA

    4. Mitochondrial DNA

  5. C bands occur in chrornosomal regions having

    1. Pseudo-alleles

    2. heterochromatin

    3. Euchromatin

    4. Polygene

  6. Match List I (Postulates) with List II (Scientists) and elect the correct answer using the codes given below

    List-I List-II
    1. Inheritance of the acquired characters

    2. Multiplication of individual species in geometrical proportion

    3. Mutation theory of evolution

    1. Hugo de Vries

    2. Julian Huxley

    3. Jean Baptiste Lamarck

    • A
    • B
    • C
      • 1
      • 2
      • 3
      • 2
      • 3
      • 1
      • 3
      • 1
      • 2
      • 3
      • 2
      • 1
  7. Gene to Gene hypothesis of host-pathogen interaction was proposed by

    1. Maclintox

    2. Flor

    3. Zadoks

    4. Agrios

  8. Which one of the following is used as biocontrol agent of soil borne pathogens?

    1. Fusarium oxysporum

    2. Trichoderma harzianum

    3. Pythium aphanidermatum

    4. Scierotium rolfsii

  9. Colletotrichum infecting sugarcane produces which of the following asexual fruiting bodies?

    1. Acervulus

    2. Pycnidiurn

    3. Sporodochium

    4. Synnemata

  10. Which one of the following pathogens infect unfertilized ovary in wheat?

    1. Puccinia graminis tritici

    2. Puccinia recondita

    3. Usilago nuda tritici

    4. Puccinia striformis

  11. The first resistance (R) gene, against Helminthosporium carborum race 1, known as Hm-1 gen was isolated from

    1. Rice

    2. Potato

    3. Maize

    4. Wheat

  12. Match List (Rice diseases) with List II (Causal organisms) and select the correct answer using the codes given below the lists:

    List-I List-II
    1. Blast

    2. Stern rot

    3. Udbatta

    4. Blight

    1. Ephelis oryzae

    2. Xanthomonas oryzae

    3. Sclerotium oryzae

    4. Pyricularia oryzae

    • A
    • B
    • C
    • D
      • 4
      • 3
      • 1
      • 2
      • 2
      • 1
      • 3
      • 4
      • 2
      • 3
      • 1
      • 4
      • 4
      • 1
      • 3
      • 2
  13. The fiber of jute (Corchrus) is obtained from the

    1. Stalks of followers

    2. Secondary phloem

    3. Secondary xylem

    4. Leaf-sheaths

  14. Which one of the following plants yields Turpentine oil?

    1. Cymboopogon Citratus

    2. Pinus roxburghii

    3. Gentum ula

    4. Operculina turpethum

  15. In which of the following parts of Himjalaya the ‘tree line’ is at the highest altitude?

    1. Estern Himalaya

    2. Kumaun Himalaya

    3. Garhwal Himalaya

    4. Western Himalaya