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[A] : A complete double circulation occu...

[A] : A complete double circulation occurs in birds for the first time.
[R]: At no point is there any opportunity for oxygenated and unoxygenated blood to mix.

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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The correct Answer is:
A
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TRUEMAN BIOLOGY-Animal Physiology -ASSERTION AND REASON
  1. [A] : Peyer's patches are derivatives of lymphoid tissue. [R]: The...

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  2. [A] : Elephants have lophodont type of teeth. [R]: There is an int...

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  3. [A] : A complete double circulation occurs in birds for the first time...

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  4. [A] : The heart of birds is more advanced than the four chambered hear...

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  5. A : Portal system consists of veins which start from capillaries and e...

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  6. [A]: in mammalian heart there is a very swift conduction of stimulatio...

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  7. [A] : Reduced blood can carry more CO2 than oxygenated blood. [R]:...

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  8. [A] : The central nervous system regulates the release of saliva from ...

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  9. [A] : Gall stones are pebble sized structures that formed in the gall...

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  10. [A] : Upon stimulation of a muscle cell, cal- cium ions (Ca^(++)) are...

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  11. [A]: Osteoporosis is a bone disorder that results from the loss of cal...

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  12. [A] : In mammals, ends of presynaptic fibres are enlarged to form syn...

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  13. [A] : Receptors located in tendons, joints and skeletal muscle give in...

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  14. [A]: Lateral-line organs are important in connection with aquatic mode...

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  15. [A] : Accomodation in the bird's eye is con- trolled by the ciliary ap...

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  16. [A] : Mammals lack mucous glands in their skin. [R] : The epidermis ...

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  17. [A] : In old age, the skin gets wrinkled. [R]: Epidermis has a sin...

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  18. [A] : In Mammals sweat glands are primarily concerned with regulation...

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  19. [A] : [A]: Spermatogenesis occurs in the seminiferous tubules of the t...

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  20. Statement 1 : In a Graafian follicle, the primary cell, the and the f...

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