By:Ahmed mohamed sahwan Fertilization By:Ahmed mohamed sahwan

Fertilization Union of male gamete (Sperm) and female gamete (ova) ,forming Zygot Site / Ampulla (Uterine tube) Duration / about 24 hours

Sperm pass rapidly from the vagina into the uterus then into the uterine tube. These movements are generated by: Movements of their tails Contractions of the uterus

About 400 sperms reach the ovum by chemobiotaxis, but only one sperm enters it to complete the fertilization process. Majority of the sperm do not make it to the egg because of many reasons including: They are destroyed by vaginal acid They go up the wrong uterine tube

Sperms must undergo some steps to be able to fertilize the ovum 1-capacitation 2-Acrosome reaction

capacitation It is the period of adaptation of sperms in the female genital tract. This period is about 7 hours. This involves removal of the glycoprotein coat and seminal proteins from the surface of the sperms acrosomes.

Acrosome reaction The sperm acrosome releases proteolytic enzymes as acrosine, hyaluronidase, esterases, and neuraminidase. Only capacitated sperms can pass through the coronal cells and cause its dispersal by the action of acrosomal enzymes.

Penetration of the zona pellucida The release of acrosomal enzymes causes lysis of zona pellucida & sperm can penetrate forming pathway to the oocyte When sperm penetrates the zona pellucida a zona reaction occurs by action of lysosomal enzymes

Intra cytoplasmic sperm injection (ICSI) is an in vitro fertilization procedure in which a single sperm is injected directly into an egg  1-to overcome male infertility problems(severe oligospermia :20-50 million sperm per milliliter) 2-may also be used where eggs cannot easily be penetrated by sperm

Made By: ahmed mohamed sahwan 102 Thank you Made By: ahmed mohamed sahwan 102