Fill in the blanks

1.  Corian and _________are the membranes formed by the growing embryo.
2. The umbilical cord connects the embryo with the _________.
3. The gestation period in human beings is 9 months or ________days.
4. The reproductive part of the flower that contains _______ or germ cells is stamens and carpels.
5. Pollen grains are spores produced by pollen ________ present in the pollen sac of the anther.
6. Pollen grain germinates on stigma and produces a _____thin-walled pollen tube, one of its two nuclei divides and forms two sperms.
7. Union of one sperm with the egg in _______is called fertilization.
8. Union of second sperm with fusion nucleus is known as double _______.
9. Continuation of life starts from cells either those of the general body or the __________.