Reproductive system is the biological system through which the process of producing children is accomplished. After the egg is fertilized it is the organs of the female body to take over complete responsibility to grow the offspring. Both the male and female bodies have very intricate systems to make the fertilization possible. This also depends on the hormones and the nervous system. Of course now days there are complete new ways to reproduce which includes having a baby without having a mate. Females can get sperm injections as well. 
Female Reproductive Organs
In a human body there are two different kinds of sex cells; which differentiate between a male and a female. These are called Gametes, the female gamete is also known as the egg, or the ovary. The ovaries are a part of the endocrine system because they give off a hormone called estrogen. For women, their reproductive organs are located inside the body, under the vulva. Unlike the male reproductive system, the entire female reproductive system is located in the pelvic area. There are many different parts to the female's reproductive system such as; the vulva. The vulva is a covering for the other internal reproductive organs. The internal reproductive organs are the vagina, uterus, fallopian tubes, and ovaries. The uterus contains some of the strongest muscles in the female body, they can also grow and expand to help push a baby out during labor. There are two tubes connected to each side of the uterus, called the Fallopian tubes. These tubes are used for a sort of passageway for the egg to travel to the uterus.  After an egg is fertilized, it is called a zygote.
Every female will go through this every month after they reach puberty. This is basically a way of seeing if a woman is pregnant or not. It will take out and egg from the woman and it will sit in the fallopian tube until it is dried, then will be exited out of the body through menstruation. For an average woman it will last around 3-5 days out of a month. The reason females tend to get a little upset or in a bad mood during this time is because the hormone, estrogen, goes crazy and makes females feel tired and very irritable.
Male Reproductive Organs
The male reproductive organs have a different placement then the females. The females are all inside the pelvic area, while the male's are on the inside as well as the outside. The main part of the male reproductive system would be the testicles. After the male gets old enough the testes will produce and store many little sperm cells inside. The testes are also part of the endocrine system because they give off the hormone, Testosterone. The males reproductive organs will work together to release semen into the female, which cause the egg inside the female to be fertilized.
Development of Sex Cells
The development of the sex cells has to have both the male and the female to work. Together the male and female use their reproductive organs to fertilize the egg; which then becomes known as the zygote. There are 46 chromosomes injected into the egg in this process. Half from the male and half from the female, this is also known as the genetic material which makes up the new individual to be created. 
In the male, you can get cysts, pseudohermaphroditism, adrenal tumors, anorchism, and more. In the female, you can inherit diseases in their labia minora, meaning they will seal together. Or a defected hymen which causes distention of the uterus; this is called hydrometrocolpos and hematocolpometra. Also the commonly known disease for a woman or a man to get is infertility, which mean they are prevented from having children. For men infertility is usually caused by deficiencies in the sperm production. For a women it is usually because of deficiencies producing the ovaries. On top of all these you can also obtain a sexually transmitted disease(STD). And std is caused when you are not careful or using protection. Some of the main types of std's are syphilis, gonorrhea, genital herpes, and aids. There are several different cancers both the male and the female can get that affect their reproductive organs. In the male, you can get testicular cancer, which are tumors that grow inside the testicles. Another would be prostate cancer, which is when one of the hormones called androgen, somewhat goes out of control, which causes tumors in the prostate. 
- Reproductive System Information A.D.A.M., adam, 2001.
- About Human Reproduction Steven Dowshen, MD, Kid's Health, May 2010.
- Components of the Female Reproductive System Steven Dowshen, MD, Kid's Health, May 2010.
- What the Male Reproductive System Does Steven Dowshen, MD, Kid's Health, May 2010
- Reproductive System Disease Sir Stanley George Clayton, M.D., John Kingsley Lattimer, M.D., Nicholas A. Romas, M.D., Encyclopædia Britannica, 18 Feb. 2011