(a) Fertilization :

• Sperm comes in contact and enters the secondary oocyte.
• Activates/induces secondary oocyte to complete meiosis II leads to formation of ovum/ootid.
•  The haploid nucleus of sperm and that of ovum fuse to form a diploid zygote completing the process of fertilization.

Implantation:

• Trophoblast layer of blastocyst attaches to the endometrium (of the uterus).
• The uterine cells divide rapidly and cover the blastocyst.
• The blastocyst becomes embedded in the endometrium and the implantation is completed.
• (b)  hCG (human chorionic gonadotropin)
• hPL (human placental lactogen)
• estrogen
• progestogens

Detailed answer : 

(b) The placenta also acts as an endocrine gland because it produces many hormone-like human Chorionic- Gonadotropin (hCG), human placental Lactogen (hPL), Oestrogen and progesteron and estrogen etc. In the later phase of pregnancy a hormone called as relaxin is also secreled by the ovary, hCG, hPL and relaxin hormone are produced in women only during pregnancy.