The Reproductive System

Keywords

Reproductive system, procreation, penis, vagina, sperm, ova, egg, prostate, testicles, testes, sexual intercourse, fallopian tubes, ovaries, uterus, cervix, pregnancy.

Introduction

Humans need to procreate in order for the survival of the species. As with other species, this is a given. For us to be able to do that, we need a reproductive system. We know that we have male and female genders, and these each have their own components.

The Male Reproductive System

The male reproductive system comprises of:

Externally, all you can see of the male reproductive system is the penis and the testes (encased in a scrotum - commonly called the ball bag). This enters the vagina, in what is known as penetrative sexual intercourse.

When a man climaxes, he exerts sperm from the testes, through the urethra and out the end of the penis. This then enters the vagina. For the man, this is biologically all he has to do to reproduce.

Interesting fact: in the animal kingdom, to mate, an octopus will literally rip its penis off, throw it at the female, and grow a new penis.

The System Roles

Let's take a look at the roles of the male reproductive organs:

Sperm: the sperm is what is exerted from the penis upon climax during intercourse. This is a single-cell gamete that finds the ova in the female reproductive system.

Testes: these are what store and create the sperm. There is more on what sperm does in the DNA and Cells section of the website. The testes also creates testosterone, a hormone that allows the man to enter puberty and grow masculine features such as pubic hair, facial hair and gives them a change in voice.

The penis: this is an intromittentAllows for insertion into the vagina. organ that allows for sexual intercourse. It also acts as the urinal duct for a male.

The prostate: a gland that produces seminal fluid that mixes with sperm to make semen. Testosterone controls how the prostate works.

The Female Reproductive System

Females have a more complex system than the males, as they hold the embryo and foetus during pregnancy, and give birth. It comprises of:

In similar fashion to the male system, the female system also has a climax, and will exert fluid during climax. Once the sperm has entered the female reproductive system, they will travel up to the cervixThe lower part of the vagina.. A male can ejaculate up to 200 million sperm each time, but only around 2 million sperm will reach the cervix, as they have to flow through acidic fluid inside the vagina.

The sperm then have to find their way up to the top of the organ, the uterusThe upper area of the vagina., and only around 10,000 make it there. They are continually attacked by white blood cells and absorbed by the phagocyteA white blood cell of the immune system..

By the time they reach the fallopian tubes, there are now just 5,000 sperm left. They have travelled up through the vagina, the cervix, the uterus and now they face their biggest challenge - attaching to the egg. All along the fallopian tube, sperm will have either petered out and given up, or will find themselves attached to the tube itself, as it is covered with a layer of mucus.

So, while all of this happens, each interaction with sperm is undertaken with the white blood cells, and a woman's immune system to fight off infection.

So, Now What?

Well, this is where the one egg, and the one sperm form an embryo and in a few weeks' time, it will be a foetus, which by that point, it will be considered a baby, and the female is pregnant.

Interesting fact: the umbilical cord has 2 arteries and 1 vein, linking the mum with the baby. The vein transports oxygen and nutrients to the baby, and the arteries remove waste material via the mother's kidneys.

It takes 9 monthsThe longest known pregnancy lasted for 375 days, in 1945. to conceive and go a full term in pregnancy. In this time, the baby develops in the womb (uterus), and then when ready, the vagina will dilate to up to 10cm, and allow for passage of the new born baby.