Class 12 Biology MCQs Chapter – 5
61. The ratio of phenotypes in F2 of a monohybrid cross is :
( A ) 3 : 1
( B ) 1 : 2 : 1
( C ) 9 : 3 : 3 : 1
( D ) 2 : 1
ANS-( A )
62. A pure tall pea was crossed with a pure dwarf pea . All the plants of F1 were found to be tall . This is due to :
( A ) Dominance
( B ) Disappearance of factor for dwarfness in F1 generation
( C ) Segregation of factors
( D ) Co – ordination
ANS-( A )
63. Sickle cell anemia shows
( A ) Epistasis
( B ) Co – dominance
( C ) Pleiotrophy
( D ) Incomplete dominance
ANS-( C )
64. The distance between the genes is measured by :
( A ) angstrom
( B ) map unit
( C ) Dobson unit
( D ) millimeter
ANS-( B )
65. The percentage of ab gamete produced by AaBb parent will be
( A ) 25 %
( B ) 50 %
( C ) 75 %
( D ) 12.5 %
ANS-( A )
66. Which of the following is a test cross ?
( A ) TT x TT
( B ) Tt x Tt
( C ) tt x tt
( D ) Tt x tt
ANS-( D )
67. Number of Autosomes present in Liver cells of a human female is :
( A ) 22 Autosomes
( B ) 22 pairs
( C ) 23 Autosome
( D ) 23 pairs
ANS-( B )
68. A person suffering from colour blindness can not recognise :
( A ) red & yellow colours
( B ) red & green colours
( C ) blue & green colours
( D ) None of these
ANS-( B )
69. In human blood group AB :
( A ) antibodies are present
( B ) antibodies are absent
( C ) antibody a is present
( D ) antibody b is present
ANS-( B )
70. Mendel proposed
( A ) Law of linkage
( B ) 10 % energy law
( C ) Laws of inheritance
( D ) none of these
ANS-( C )
71. Who is regarded as ‘ Father of Genetics
( A ) Mendel
( B ) Morgan
( C ) Lamarek
( D ) De Vries
ANS-( A )
72. The number of different type of gametes produced from a plant with genotype AaBbcc is :
( A ) 2
( B ) 8
( C ) 4
( D ) 16
ANS-( A )
73. How many types of gametes are expected from the organism with genotype AABBCC ?
( A ) One
( B ) Two
( C ) Four
( D ) Eight
ANS-( A )
74. A haploid set of all the genes present in a gamete is called
( A ) Genotype
( B ) Phenotype
( C ) Genome
( D ) Linkage group
ANS-( C )
75.Number of characters studied by Mendel in Pea was ?
( A ) 5
( B ) 7
( C ) 6
( D ) 4
ANS-( B )
76. The The genotypic ratio of a monohybrid cross will be
( A ) 3 : 1
( B ) 1 : 1
( C ) 1 : 2 : 1
( D ) 2 : 1
ANS-( C )
77. Mendel’s law of segregation is based upon the F ratio of :
( A ) 1 : 2
( B ) 9 : 3 : 3 : 1
( C ) 1 : 2 : 1
( D ) 3 : 1
ANS-( D )
78. Genes do not occur in pairs in :
( A ) Zygote
( B ) Somatic cell
( C ) Endosperm cells
( D ) Gametes
ANS-( D )
79. Segregation of genes take place during
( A ) Metaphase
( B ) Anaphase
( C ) Prophase
( D ) Embryo formation
ANS-( B )
80. A cross between hybrid and a parent is known as :
( A ) Monohybrid cross
( B ) Back cross
( C ) Test cross
( D ) Reciprocal cross
ANS-( C )
