In the male, sperm are produced in the testes and conveyed to the female in a fluid called semen, which passes out of the body through the penis. Other parts of the male reproductive system include the prostate gland, the scrotum, and the urethra.
In the female, the eggs, or ova are produced in the ovaries and released during ovulation into the fallopian tubes about halfway through the menstrual cycle. If fertilization occurs, the resulting zygote travels down the fallopian tube to the uterus, where it implants and continues development. If the ovum is not fertilized, it continues its journey toward the uterus, where it degenerates and is released in the menstrual flow through the vagina during menstruation.
The cœlenterata, as we saw in hydra, had developed rude digestive and reproductive systems.
It is an incidental result of differences in the reproductive systems of the parent-species.
The reproductive system of animals differs widely from that of plants, but both are reproductive systems.
This allows the increase in the size of the segment corresponding to the varying size of the digestive and reproductive systems.
The digestive and reproductive systems have thus nearly attained their final form.