S3.4.4 Chapter 4

Reproductive systems

What are the parts of the reproductive system, and what does each one do?

Your guess

Pick one before you read on. It is fine to be wrong.

Your guess

A The ovaries hold eggs, the testes make sperm, and a baby grows in the uterus.
You picked A. Read on. At the end, the chapter comes back to your guess.
B The uterus makes the eggs, and a baby grows in the ovaries.
You picked B. Read on. At the end, the chapter comes back to your guess.
C In a girl, urine and periods leave the body through the same opening.
You picked C. Read on. At the end, the chapter comes back to your guess.

By the end you can

Label the main parts of the male and female reproductive systems
State the job of the testes, ovaries and uterus

The reproductive system is the organ system that makes new life. A female system and a male system are different. Each makes a special cell. One cell from each is needed to start a baby.

Draw it first

Draw the female reproductive system

1 Draw two ovaries, one on each side, low in the abdomen.
2 Draw an oviduct from above each ovary. Its open end is fringed.
3 Join both oviducts to the top of the uterus. Draw the cervix at its bottom.
4 Draw the vagina, from the cervix down to the outside of the body.

The two ovaries hold hundreds of thousands of eggs. From puberty, about once a month, one ovary lets go of one egg. Only about 400 are ever let go.

Each oviduct is a narrow tube, also called an egg tube or a fallopian tube. It carries the egg from the ovary to the uterus.

The uterus, or womb, is a hollow organ with a thick wall of muscle. A baby grows in it. It has a soft lining inside. The cervix is the narrow neck at the bottom of the uterus. The vagina is a stretchy tube from the cervix to the outside of the body.

The female reproductive system. It lies low in the abdomen, inside the bones of the hips.

Outside, between the legs, is the vulva. It has two pairs of skin folds, the outer labia and the inner labia. Inside them, from the front, is the clitoris. Next is the small opening of the urethra, then the opening of the vagina.

Urine leaves through the opening of the urethra. Period blood leaves through the opening of the vagina. They are two different openings.

A male has two testes. One is called a testis. They hang outside the body in a bag of skin, the scrotum. From puberty on, the testes make sperm, millions every day. The sperm are stored in the epididymis, a coiled tube on the back of each testis. Sperm are made best a little cooler than the inside of the body. That is why the testes hang outside.

Each sperm duct carries sperm from the epididymis, up and round the bladder, to the urethra. It is also called the vas deferens. On the way, glands add a fluid. These glands are the seminal vesicles and the prostate gland. Sperm and this fluid together are semen.

The bladder stores urine, which comes down from each kidney in a tube called the ureter. The urethra is a tube from the bladder through the penis to its tip. It carries urine out of the body. At other times it carries semen. It never carries both at once.

The male reproductive system, seen from the side. Only one testis shows, because the other is behind it.

The main parts and their jobs.

See it three ways

As a picture

In words

An ovary lets go of an egg. The open end of the oviduct catches it, and the oviduct carries it toward the uterus.

In symbols

ovary → oviduct → uterus

Try it

Label the systems from memory

You need: paper, a pencil.

Copy the outline of the female system and the male system onto paper, with no labels.
Close the book. Label as many parts as you can, and write one job next to each.
Open the book and check. Fix any you missed, then try again tomorrow.

What you will see: Most people need two or three tries. Saying each name as you write it helps you remember it.

If you cannot try it, this is what happens.

A wrong idea many people have

A girl passes urine and her period through the same opening.

Why it feels right: The two openings are small and close together, between the legs.

The test that breaks it: Look at the drawing of the vulva. The opening of the urethra is in front of the opening of the vagina, and apart from it.

What is true: Urine leaves through the urethra. Period blood leaves through the vagina. They are two different openings.

Key words

reproductive system: the organ system that makes new life.
ovaries: two organs that hold the eggs. One is an ovary.
oviduct: a tube that carries an egg from an ovary to the uterus. It is also called a fallopian tube.
uterus: the hollow organ, also called the womb, where a baby grows.
testes: two organs in the scrotum that make sperm. One is a testis.
sperm duct: a tube that carries sperm from a testis to the urethra. It is also called the vas deferens.

Back to your guess

The answer is A: The ovaries hold eggs, the testes make sperm, and a baby grows in the uterus.

The ovaries hold the eggs and the testes make sperm. A baby grows in the uterus. Urine and periods leave a girl's body through two different openings.

Keep it

Copy this into your exercise book.

Ovaries hold eggs. Oviducts carry eggs to the uterus, where a baby grows. The cervix opens into the vagina. Testes in the scrotum make sperm. Sperm ducts carry sperm to the urethra, which runs through the penis.

Draw: Draw the female system from the front and label six parts.