40. Fertilization. Internal fertilization in mammals.

Question 1

Internal fertillization in mammals

Answer 1

Process:

-Fusion of egg and sperm genetic material.
-Occurs in the distal fallopian tubes.
-Ovum Lifespan: 20-24 hours.
-Sperm Survival: Up to 5 days in the female reproductive tract.

Main Results:
-Restores diploid chromosome number.
-Determines gender.
-Initiates division.
-Ovum degenerates if unfertilized.

Preceded by:
-Ovulation: Release of mature oocyte into fallopian tube.
-Sperm Deposition: In the female reproductive tract.
-Capacitation: Removal of glycoproteins and plasma proteins from sperm, enabling acrosome reaction and fertilization.
-Sperm Movement:
Influenced by estrogen.
Uterine and fallopian tube contractions (cilia).