Oxford based explanation of the reproductive system, male and female. 6ht grade natural sciences

1. reproduction
Unit 3. Natural Sciences

2. What is reproduction?
• One of the three vital functions
• Interaction
• Nutrition
• Reproduction
• Types:
• Asexual: one living being can
produce offspring (descendencia)
(bacteria, plants, protoctist, fungi)
• Sexual: two living being (male and
female) are needed to produce
offspring (descendencia) (animals
and plants, algae, fungi)
• Definition: it is a vital function that consists on
the creation of new living beings from previous
ones.

3. Sexual characters
 Primary characters:
 The reproductive organs: female and male reproductive organs are different since they are
born. (Ovaries and testes respectively)
 Secondary characters:
 They appear in puberty (girls and boys between 9-16, ussually around 11)
 Classify these characters in male, female and both)
Facial hair, pubic hair,
wider hips, deeper
voice, underarm hair,
wider shoulders,
breasts, chest hair.
Female Male

4. Reproductive cells
Female gametes: egg cells
 Produced in the ovaries each 28
days
 Around 400 egg cells mature
 50-55 years, women stop
producing egg cells
Male gametes: sperm cells
 Sperm cells are made in the
testes.
 Production doesn't stop
 Semen is
 2% sperm cells
 98% seminal fluid (produced in
seminal vesicles)

5. Fertilization (video)
Human beings have 46 cromosomes in the
DNA of each cell of the body.
Gametes have only 23 cromosomes.
ovule
Sperm
cell
zygote
23
cromosom
es
23
cromosom
es
46
cromosom
es
zygote
embryo
fetus

7. External female organs

8. Menstruation cycle
Day 1-
5
menstruation
Day 6-
14
Egg cell matures Uterus thickens
Day
14-28
ovulation
ovulation
Fetilisation zygote embryo fetus
Not fertilised
Menstruation
again

9. Pregnancy
 40 weeks.
 Placenta: provides
oxygen and nutrients
and takes away
carbon dioxide and
waste.
 Umbilical cord
 Amniotic bag:
contains amniotic
fluid that protects
the fetus.
zygote
embyo
fetus

10. Birth
 The walls of the uterus contract
 The cervix gets wider
 The amniotic sac breaks
 The contractions push the baby into the
vaginal canal.
 The baby is expelled: head first.
 The doctor cuts the umbilical cord.
 The amniotic sac, the placenta and the rest
of umbilical cord are expelled.

11. Medical
advances in
reproduction
• In vitro fertilisation
Fertilisation:
• Caesarean (for breech birth)
Birth:
• Amniocentesis
Pregnancy:
• Blood and urine tests
• Ultrasound scan
Healthcare:
Family planning (contraception)

12. Natural contraception
 Calendar based
 Symthom based
Temperature
Secretion
 Abstinence
 Lactation
Don't prevent
sexual illnesses
NOT RELIABLE
(HIGH NUMBER
OF
IRREGULARITIES)

13. Artificial contraception
 HORMONAL
 PILL
 RING
 IMPLANTS OR PATCHES
 BARRIER METHODS: avoid the join of male and female gametes
 MALE CONDOM (also prevent sexual ilnesses)
 FEMALE CONDOM
 MIXED
 IUD (DIU) INTRAUTERIN DEVICES
HIGH
EFFECTIVENESS
CONDOM PREVENTS
SEXUAL ILLNESSES