Human reproduction involves the combining of male and female sex cells through sexual reproduction. During puberty, between ages 11-15, individuals develop primary and secondary sex characteristics that allow for reproduction. The female reproductive system includes the ovaries, uterus, fallopian tubes, vagina, and vulva. The male reproductive system includes the testicles, vas deferens, urethra, seminal vesicles, and prostate. Fertilization occurs when sperm meets an egg in the fallopian tubes. A fertilized egg implants in the uterus and develops over 9 months into a baby, receiving nutrients from the placenta via the umbilical cord. Birth occurs in three stages of dilation, expulsion, and afterbirth

1. Unit 4 human
reproduction
María Boizas Crespo

2. Human reproduction
 Living things create other
living things in the process of
reproduction.
 Human beings reproduce
through sexual reproduction ,
bringing male and female sex
cells together.

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

4. Secondary sexual
characteristics
 The external characteristics
wich differentiate men from
women are called secondary
sexual characteristics.
 During puberty,between the
ages of eleven and fifteen,the
reproductive system matures.

5. Changes during puberty
 Some changes are the same
for both sexes like:
 Growing taller.
 Hair growing in the armpit.
 Other changes are specific to
each sex:
 Girlsdevelop breasts and their
hips get wider.
 Boys get deeper voices.

6. The reproductive
cells:sperm
 Sperm are the male
reproductive cells.They have
a head and a long tail called a
flagellum.They are produced
in large numbers from the
time of puberty.

7. The reproductive cells:ova
 Ova are the female reproductive
cells.They do not move.from
puberty,an ovum matures every
month.

8. 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 conects the
ovaries to the uterus.
 The vagina conects the uterus
to the outside of the body.
 The vulva is the external part of
the female reproductive system.

10. 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
scrotum.
 The vas deferens take the 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 urethra.
 The penis is outside the male
reproductive system.

12. Pregnancy (I)
 Pregnancy lasts about 9
months and ends in a birth.
 During the early stage
different structures are
created to protect the
embryo:
 The placenta takes nutrients
from the mothers blood to the
embryo.
 The umbilical cord connects the
placenta to the embryo.
 The amniotic sac protects the

13. Pregnancy (II)
 The baby develops step by
step:
 After 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 5 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:
 Dilation:rhytmic contractions
make the opening of the vagina
and vulva big enough for the
baby to come out.
 Expulsion:the baby is born and
the doctor cuts the umbilical
cord.
 After birth:the placenta comes
out of the mother’s body.

15. The end