141. Which one pair of the following parents is most likely to get a child who suffer from hemolytic disease of new born?

1. 1. Rh-negative mother and Rh-positive father

   
   
   

   2. Rh-positive mother and Rh-negative father

   
   
   

   3. Rh-negative mother and Rh-negative father

   
   
   

   4. Rh-positive mother and Rh-positive father

   
   
   

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1. View Hint View Answer Discuss in Forum

   Hemolytic disease of the newborn occurs when a Rh^- mother conceives a Rh⁺ child. Mother’s blood starts producing antibodies against the foetal red blood cells.
   

   Correct Option: A

   Hemolytic disease of the newborn occurs when a Rh^- mother conceives a Rh⁺ child. Mother’s blood starts producing antibodies against the foetal red blood cells.
   

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142. A and B genes are linked what shall be genotype of progeny in a cross between AB/ab and ab/ab?

1. 1. AAbb and aabb

   
   
   

   2. AaBb and aabb

   
   
   

   3. AABB and aabb

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   

   Correct Option: B

   
   

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143. Probability of four sons to a couple is

1. 1. 1
      4

   
   
   

   2. 1
      8

   
   
   

   3. 1
      16

   
   
   

   4. 1
      32

      
      

   
   
   

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1. View Hint View Answer Discuss in Forum

   
   

   Correct Option: C

   
   

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144. Two non-allelic genes produce new phenotype when present together but fail to do so independently are called?

1. 1. Epistatsis

   
   
   

   2. Polygene

   
   
   

   3. Non- complimentary genes

   
   
   

   4. Complimentary genes

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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145. Ratio of complementary genes

1. 1. 9: 3: 4

   
   
   

   2. 12: 3: 1

   
   
   

   3. 9: 3: 3: 4

   
   
   

   4. 9: 7

   
   
   

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1. View Hint View Answer Discuss in Forum

   In complementary gene action, both the non allelic pair independently produce similar phenotypes and when present together produce a new phenotype. So, that F2 ratio 9: 3: 3: 1 would become 9: 7.
   

   Correct Option: D

   In complementary gene action, both the non allelic pair independently produce similar phenotypes and when present together produce a new phenotype. So, that F2 ratio 9: 3: 3: 1 would become 9: 7.
   

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