1. By Nerea silva Sanchez
and
Alicia Romero Viñas

2. Primary sexual characteristics
The reproductive systems are the primary sexual
characteristics. We already have them when we
are born and they are different for male and
female.

3. Secondary sexual characteristics
The external characteristics which
differentiate men from women are called
secondary sexual characteritics.
During puberty between the ages of eleven
and fifteen, the reproductive system
matures.
Other changes are specific to each sex:
 Girls develop breasts and their hips get
wider.
 Boys get deeper voices.

4. Reproductive cells
Reproductive cells carry out the funtion of
reproduction.
 Sperm are the male reproductive cells. They are
small. They have a head and a long tail called a
flagellum.
 Ova are the female reproductive cell. They do
not move. From puberty, an ovum matures every
month.

5. Ovum
Sperm

6. The female reproductive system
The female reproductive system is made up of
these organs:
 The ovaries produce the ova.
 The uterus is where the baby develops.
 The Fallopian tubes connect the ovaries to the
uterus.
 The vagina connects the uterus to the outside of
the body.
 The vulva is the external part of the female
reproductive system.

8. The male reproductive system
The male reproductive system is made up of these
organs:
 The testicles are outside the body. They produce
sperm. They are covered by a bag of skin called
the scrotum.
 The vas deferences take sperm from the
testicles to the urethra.
 The urethra takes the sperm outside the body.
 The seminal vesicles and prostate produce
seminal fluid and send it to the urehtra.
 The penis is outside the male reproductive
system.

10. Fertilisation
Fertilisation occurs when an ovum and a sperm
join inside the Fallopian tubes and they create a
single cell called a zygote. The zygote goes down
the Fallopian tubes, it is implanted in the wall of
the uterus and it becomes an embryo.

11. Pregnancy
Pregnancy lasts about 9 months and ends in a
birth.
During the early stages, different structures are
create to protect the embryo.
 The placenta takes nutrients and oxygen from
the mother’s blood to the embryo.
 The umbilical cord connects the embryo to the
placenta.
 The amniotic sac protects the embryo.

12. The baby develops step by step:
 Afther 3 months: The embryo has all its
organs. It becomes a foetus.
 After 5 months: The baby’s body develops
and it starts moving and the mother feels it.
 After 9 months: The baby is ready to be born
and it weighs around 3 kilos.

14. Labour
The process of giving birth is called labour.
Labour takes place in three phases:
1. Dilation: rhythmic contractions make the
opening of the vagina and vulva big enough for
the baby to come out.
2. Expulsion: the baby is born and the doctor cuts
the umbilical cord.
3. Afterbirth: the placenta comes out of the
mother’s body.

15. The end