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MODEL PAPER 6 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 61 Mark
MCQ
Assertion (A): Evolution of man is the example of progressive evolution.
Reason (R): Tapeworm is developed due to retrogressive evolution.
  • A
    Both A and R are true and R is the correct explanation of A.
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

Both A and R are true but R is not the correct explanation of A.
Explanation: Progressive evolution is the formation of more complex specialized organisms from simple and less elaborate forms. Examples: evolution of amphibians from fish like ancestors and evolution of birds and mammals from reptile-like ancestors. Retrogressive evolution is the formation of simple and less elaborate forms from more complex and specialized ones. Example: evolution of many parasitic organisms like tapeworm which does not have digestive system. It absorbs food through body surface.

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