Competitive Exams: Botany MCQs (Practice-Test 47 of 104)

  1. Living organisms contain only

    1. L-amino acids and L-sugars

    2. L-amino acids and D-sugars

    3. D-amino acids and D-sugars

    4. D-amino acids and L-sugars

  2. Match List I with List II and select the correct answer using the codes given below the lists:

    List-I List-II
    1. DNA Structure

    2. Semi-conservative replication of DNA

    3. One gene, one enzyme theory

    4. Induction of mutation

    1. N/A

    2. N/A

    3. N/A

    4. N/A

    • A
    • B
    • C
    • D
      • 1
      • 2
      • 3
      • 4
      • 3
      • 4
      • 1
      • 2
      • 3
      • 4
      • 2
      • 1
      • 4
      • 3
      • 2
      • 1
  3. Cultivated tobacco, Nicotine tobacco has 2n = 48 chromosomes and is amphidiploids. Nicotine Sylvester's which one of the progenitors of Nicotine tobacco has 2n = 24 chromosomes and is diploid. It has contributed one genome to Nicottama tobacco. When these two species are hybridized, the critical chromosomal associations at meiosis in the hybrid will be

    1. 24 bivalents

    2. 12 univalent

    3. 12 bivalents

    4. 12 bivalents + 12 univalent

  4. A chromosome carrying the Centro mere at one of the ends is called

    1. Met centric

    2. Telemetric

    3. Apocentric

    4. Acenthc

  5. What could be the number of phenotypic classes expected from a testcross of Aa Bb Cc hybrid?

    1. 16

    2. 12

    3. 8

    4. 4

  6. Which one of the following statements correctly defines the term autotrophic mutants?

    1. Mutant cells capable of synthesizing essential growth actors form the minimal medium

    2. Mutant cells unable to grow in the presence of axon

    3. Mutant cells incapable of producing one or two growth actors essential for growth.

    4. Mutant cells resistant to a drug

  7. The simplest way to determine the genotypes of the offspring of a cross is to use

    1. Pedigree chart

    2. Punnett square

    3. Generation chart

    4. Gene linkage

  8. Duplication of chromosomes without cell or nuclear division gives rise to the condition of

    1. Polyploidy

    2. Politely

    3. Haploid

    4. Diploid

  9. Triticale is the first man-made cereal crop. The combination of parents involved in its production is Tritium

    1. Sorghum

    2. Barely

    3. Saccharin

    4. Rye

  10. In 1969, Eric Davidson and Ray Britten proposed a model for DNA organization in Eukaryotes. One of the main features of their model is the existence of

    1. Cytoplasm genes

    2. Split genes

    3. Repetitive DNA

    4. Overlapping genes

  11. Which one of the following chromosome combinations is expected in an offspring obtained after selling a plant having AABBCCDD homologues pairs?

    1. AAAABBBBCCCCDDDD

    2. AA BB CC D

    3. AA BB C D

    4. AA BB C D

  12. Which one of the following plant breeding technologies or concepts has mostly contributed to the much acclaimed green revolution?

    1. Heterosis

    2. Male sterility

    3. Dwarf plant type

    4. Genetic engineering

  13. The distance between two nitrogen bases in a polynucleotide of DNA is

    1. 34.00A'

    2. 10.4A'

    3. 6.4A'

    4. 3.4A'

  14. Which one of the following molecular components associations is the essentially required one for protein synthesis in the cytoplasm of a cell?

    1. mRNA + rRNA + tRNA + DNA

    2. mRNA + rRNA + tRNA + an amino acid

    3. mRNA + polysomes + tRNA + protein bodies

    4. mRNA + tRNA + sRNA + protein bodies

  15. Which one of the following genetic units moves from one chromosome to another or from one replica to another and causes genetic changes?

    1. Muto0n

    2. Replicon

    3. Cistron

    4. Transpose