Search results
Results From The WOW.Com Content Network
In many species, the vas deferens ends in a small sac for storing sperm. [21] The only vertebrates to lack any structure resembling a vas deferens are the primitive jawless fishes, which release sperm directly into the body cavity, and then into the surrounding water through a simple opening in the body wall. [21]
The semen is stored here until ejaculation occurs. Muscles at the base of the penis contract in order to propel the seminal fluid trapped in the prostatic urethra through the penile urethra and expel it through the urinary meatus. The ejaculate is expelled in spurts, due to the movement of the muscles propelling it.
The sperm binds through the corona radiata, a layer of follicle cells on the outside of the secondary oocyte. The corona radiata sends out chemicals that attract the sperm in the fallopian tube to the oocyte. It lies above the zona pellucida, a membrane of glycoproteins that surrounds the oocyte. [14]
The human sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell with 46 paired chromosomes. In mammals, sperm is stored in the epididymis and released through the penis in semen during ejaculation. The word sperm is derived from the Greek word σπέρμα, sperma, meaning "seed".
The sperm and the ovum are known as the gametes (each containing half the genetic information of the parent, created through meiosis). [citation needed] The sperm (being one of approximately 250 million sperm in a typical ejaculation) travels through the vagina and cervix into the uterus or fallopian tubes. Only 1 in 14 million of the ...
Through differences in chromosome count, mutations or environmental influences, there is wild variation in sex hormone levels and the body’s ability to respond to them. ... When a sperm and egg ...
Sperm leave the seminiferous tubules in the dilute secretions of Sertoli cells. The rete testis does modify the luminal fluids with a limited amount of secretion and reabsorption, but their primary function is to mix and transport the sperm into the efferent ductules, where the major function is reabsorption of about 95% of the fluid, which ...
The sperm then travels through the vagina and cervix into the uterus or fallopian tubes for fertilization of the ovum. Upon successful fertilization and implantation, gestation of the fetus then occurs within the female's uterus for approximately nine months, this process is known as pregnancy in humans.