Assertion   :       Embryonic development proves interrelationship and common ancestory of metazoans.

Reason      :       It involves similar sequence of five dynamic processes during development.

1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
3. If the assertion is true but the reason is false
4. If both the assertion and reason are false

Assertion   :       There is generally monospermy in most of animals.

Reason      :       Vitelline membrane of ovum checks polyspermy.

Assertion   :       Penetration of sperm into ovum is a chemical process.

Reason      :       Acrosome of sperm secretes a lytic enzyme hyaluronidase which dissolves vitelline membrane of ovum.

Assertion :     Cleavage is also called fractionating process.

Reason    :     In cleavage, number of blastomeres increases but size of blastomears decreases.

Assertion   :       Nuclear-cytoplasmic ratio decreases in cleavage.

Reason      :       During cleavage, cytoplasmic synthesis is faster than DNA synthesis.

Assertion   :       Implantation is the process of attachment of blastocyst on uterine endometrium.

Reason      :       Implantation is controlled by trophoblast and occurs by decidual cell reaction.

Assertion   :       Gastrular movements are morphogenetic.

Reason      :       During gastrulation, cells move in masses and towards definite direction.

Assertion   :       Asexual reproduction is also called blastogenesis.

Reason      :       In asexual reproduction, there is no  fusion of gametes.

Assertion   :       Sexual reproduction is advantageous than asexual reproduction.

Reason      :       It is rapid mode of reproduction while asexual reproduction is slow mode of reproduction.

Assertion   :       In human male, testes are extra-abdominal and lie in scrotal sacs.

Reason      :       Scrotum acts as thermoregulator and keeps testicular temperature lower by 2°C normal spermatogenesis.