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[A]: The natural hybrids of the species ...

[A]: The natural hybrids of the species are either totally absent or are very rare.
[R]: Because members of separate species do not interbreed usually

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

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A
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A : Transmission of the nerve impulse across a synapse is accomplished by neurotransmitters . R : Transmission across a synapse usually requires neuro transmitters because there is space , i.e., synaptic cleft, that separates one neuron from another .

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TRUEMAN BIOLOGY-Genetics-ASSERTION AND REASON
  1. [A]: Darwin held that small favourable varia- tions formed the raw mat...

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  2. Assertion : A single mutation may produce a new species . Reason : M...

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  3. [A]: Isolation prevents inbreeding among the otherwise potential mates...

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  4. [A]: lnterspecific mating often produces a more vigorous but sterile F...

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  5. [A]: Basis of adaptation is the pre existing gene mutation. [R]: ...

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  6. [A]: Artitical selection is done only in animal breeding. [R]: Ar...

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  7. [A]: Presence of tail in children is a vestigial character. [R]: T...

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  8. [A]: Mimics are always or more often defenceless. [R]: Mimics are...

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  9. [A]: The process of speciation occurs in allopatric populations. ...

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  10. [A]: The establishment of reproductive isola- tion is an event of biol...

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  11. [A]: Random mutations together with genetic drifts and selection press...

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  12. [A]: Varied groups of plants and animals ei- ther related or unrelated...

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  13. [A]: The natural hybrids of the species are either totally absent or a...

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  14. [A]: The earliest living organisms were structurally simple. [R]:...

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  15. [A]: There is no phenomenon like organic evolution. [R]: Evolutio...

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  16. Assertion : Human ancestors never used their tails and so the tails ex...

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  17. Assertion : Comparative biochemistry provides a strong evidence in fav...

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  18. Assertion : Darwin's finches show a variety of beaks suited for eating...

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  19. Assertion:Human and great apes have a common ancestry. Reason:Man a...

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  20. Assertion:Man has descended from monkeys. Reason:Monkeys resemble hu...

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