35. Assertion : Mitochondria and chloroplasts are semiautonomous organelles. Reason : They are formed by division of pre-existing organelles as well as contain DNA but lack protein synthesizing machinery

(a)       If both the assertion and the reason are true and the reason is a correct explanation of the assertion

(b)       If both the assertion and reason are true but the reason is not a correct explanation of the assertion 

(c)        If the assertion is true but the reason is false

(d)       If both the assertion and reason are false

(e)       If the assertion is false but reason is true

      Ans.     (c)   Mitochondria and chloroplasts both are double membrane organelles. They are semi autonomous as both their structrue and functions are partially controlled by nucleus of the cell and partially themselves. Both possess their own DNA and arises from pre-existing cells. Synthesis of many amino acids occurs in mitochondria. The first formed amino acids are glutanic acid and aspartic acid.

Also plastid manufactures some of its own proteins, enzymes and other chemicals because of the presence of 70s ribosomes which can help translate the coded information contained in mRNAs transcribed over chloroplast DNA.

DNA replication is the process of forming carbon copy of DNA. Whereas transcription is the formation of RNA over DNA template.

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