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[A]: It is not possible to take photogra...

[A]: It is not possible to take photograph and count chromosomes when they are highly coiled and condensed.
[R]: Each individual of a species has a variable number of chromosomes.

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

Text Solution

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The correct Answer is:
D
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TRUEMAN BIOLOGY-Genetics-ASSERTION AND REASON
  1. [A]: The sex linked genes are passed on to the grandson through the da...

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  2. Assertion : Mutations are necessary for the survival to the species. ...

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  3. [A]: It is not possible to take photograph and count chromosomes when ...

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  4. [A]: Neurospora is an ideal genetic material for research. [R]: Bec...

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  5. [A]: Heterosis is superiority of F1 hybrid over its two genetically d...

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  6. [A]: Mendelian recombinations are due to crossing over. [R]: Crossi...

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  7. [A]: Genes confined to differential region of homologous chromosomes a...

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  8. [A]: Chromosomes appear longer during telophase. [R]: The term chro...

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  9. [A]: Copy choice theory for crossing over was proposed by Belling. ...

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  10. [A]: Kornberg and Ochoa got Nobel Prize in the field of genetics. [...

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  11. Consider the following statements : Assertion (A) : Amber codon is a...

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  12. [A): DNA replicates after mitosis. [R]: In mitosis, the chromosomal...

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  13. [A]: DNA code is copied in the synthesis of tRNA. [R]: tRNA moves o...

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  14. [A]: DNA is associated with proteins. [R]: DNA wound around histone ...

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  15. [A]: Translocation involves transfer of genetic material between homol...

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  16. Assertion : Left-handed DNA is known as B-DNA. Reason : Right - han...

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  17. [A]: Meselson and Stahl tested the Watson and Crick Theory of DNA repl...

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  18. Assertion (A) : Adenine cannot pair with cytosine. Reason ® : Becaus...

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  19. Assertion : DNA is associated with proteins. Reason : DNA binds aro...

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  20. Assertion. The genetic code is degenerate. Reason. Most amino acids ...

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