Respiratory system 3ESO Science bilingue

1. Nutrition function II

2. We have just studied the DIGESTIVE SYSTEM.
Its function is to get nutrients from food.
To transform NUTRIENTS INTO ENERGY, in the
mitochondria, our cells NEED OXYGEN.
These molecules are essential for cellular
respiration: the process through we obtain
energy.

3. In respiration, oxygen is consumed to
release energy (ATP) from nutrients,
and carbon dioxide is produced.
The respiratory system is also in charge
of expelling that carbon dioxide that
we don’t need.

5. The respiratory system.
https://www.youtube.com/watch?v=hc1YtXc_8
4A

6. Our respiratory systems consists on:
 The AIRWAYS: The air passes through this
tube or pipe. They are:
◦ Nasal cavity
◦ Pharynx (shared with digestive system)
◦ Larynx
◦ Trachea
◦ Bronchi
◦ Bronchioles
 The LUNGS: Organs that contain bronchi,
bronchioles, pulmonary alveoles and
capillaries.

7.  Nasal cavity: In here air is
◦ Filtered by cilia and mucus. The nasal cavity is
covered with a respiratory mucosa lined with a
ciliated columnar epithelium.
◦ Warmed by capillaries in that tissue.
◦ Moistened.
Is in this part of our body where sense of smell
resides.
 Pharynx: Tract shared with digestive system.
Communicates nasal and oral cavity.

8.  Larynx. Separated from the oesophagus by
the epiglottis. In here we find the vocal cords.

10.  Trachea. Tube surrounded by rings of
cartilage that keep it open. It is also covered
by mucus, that traps foreign particles, and
force them out.

12. Inspiration and expiration.
https://www.youtube.com/watch?v=SWJHSTAW
TCk
Lungs model. Pulmonary ventilation.
https://www.youtube.com/watch?v=DAR9Ne5
7Cl4

13. Lungs are formed by lobes. The right one is
formed by 3 lobes, and the left one by two.
As we have our heart is pointed slightly to the
left in our chest, the left lung is smaller that
the right one.
Lungs are
surrounded by
pleurae, two
membranes
separated by a fluid.

14. Once the air enter the lungs, it passes through
the bronchi, bronchioles and alveoli, whre
GAS EXCHANGE takes place.
This gas exchange is produced through a
DIFFUSION process.

16. What is diffusion through the
membrane?
Diffusion is a form of transportation of certain
substances through the cell membrane.

17. Inside Outside
Cell
membrane
HIGHER
concentration
LOWER
concentration
Inside
Outside
Cell
membrane
HIGHER
concentration
LOWER
concentration
Diffusion through the membrane
Diffusion is the process where substances pass from one side of a membrane where
the concentration is higher to the other side where the concentration is lower.
If the concentration of a substance is higher on
the outside, the substance enters.
If the concentration of the substance is higher on
the inside, the substance leaves.

18. After inhalation, the concentration of O2 in the alveoli is higher than in the
capillaries. The O2 therefore passes by diffusion from the alveoli into the blood.
Inside the alveolus
Membrane of the
alveolus
Diffusion of O2 during gaseous exchange
Blood
O2
HIGHER concentration
of O2
LOWER concentration
of O2
Oxygen (O2) is transported by diffusion from the alveoli into the
blood.
* Blood does not
only transport
oxygen, but
also carbon
dioxide. So…

19. The blood that goes to the lungs has a higher concentration of CO2
than that outside the alveoli. Therefore, the CO2 passes into the
alveolus.
Diffusion of CO2 during gaseous exchange
CO2
Membrane of the alveolus
LOWER concentration
of CO2
HIGHER concentration
of CO2
Inside the alveolus Blood
The carbon dioxide (CO2) is transported by diffusion from the
blood to the inside of the alveoli.

20. Diffusion inside the lungs.
https://www.youtube.com/watch?v=d-
f3RL0KiUg

21. I HOPE YOU
ENJOYED!!!
Sources:
Anaya digital.
Biology and Geology Oxford CLIL ESO 3
Video links on youtube
Just for educational purpose.