Assertion : The primitive atmosphere was reducing one i.e. without oxygen.

Reason : In the primitive atmosphere, oxygen was involved in forming ozone layer.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Mammalian ova produces hyaluronidase.

Reason : The eggs of mammal are microlecithal and telolecithal.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false.

Assertion : Protandry and protogyny ensures cross fertilization.

Reason : Cross fertilization introduces variation in progeny.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Restriction enzymes cut the strand of DNA to produce sticky ends.

Reason : Stickiness of the ends facilitates the action of the enzyme DNA polymerase.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Pollen mother cells (PMCs) are the first male gametophytic cells.

Reason : Each PMC gives rise to two pollens.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : A gamete may carry either of the traits but not both.

Reason : This is Mendel's second law or law of independent assortment.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Amniocentesis is a process of foetal sex determination.

Reason : Metabolic errors and other diseases can be diagnosed prenatally by this process.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Bursa fabricii lies on the ventral side of the cloaca in birds.

Reason : Bursa fabricii is related with flight adaptation.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Jave Apeman, Peking man and Heidelberg man are the fossils of Homo erectus.

Reason : Homo erectus evolved from Homo habilis.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false

Assertion : Emasculation prevents self- pollination in flowers.

Reason : Emasculation is the removal of anthers from a bisexual flower.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false.