IX STANDARD KERALA SYLLABUS

1. WELCOME

2. THE HUMAN RESPIRATORY
SYSTEM
THE HUMAN RESPIRATORY SYSTEM

3. SUBMITTED TO
Dr.PADMAPRIYA .P.V
N.S.S TRAINING COLLEGE
PANDALAM
SUBMITTED BY
ANJANA VIDYADHARAN
NATURAL SCIENCE
N.S.S TRAINING COLLEGE
PANDALAM

4. THE HUMAN RESPIRATORY
SYSTEM UNIT

5. FRIENDS DO YOU KNOW
WHAT IS RESPIRATORY
SYSTEM

6. The Human Respiratory System
Respiratory system (or ventilatory system) is a biological
system consisting of specific organs and structures used
forthe process of respiration in an organism. The
respiratory system is involved in the intake and exchange
of oxygen and carbon dioxide between an organism and the
environment.
In air-breathing vertebrates like human beings, respiration
takes place in the respiratory organs called lungs. The
passage of air into the lungs to supply the body with oxygen
is known as inhalation, and the passage of air out of the
lungs to expel carbon dioxide is known as exhalation; this
process is collectively called breathing or ventilation. In
humans and other mammals, the anatomical features of
the respiratory system include trachea, bronchi,

7. bronchioles, lungs, and diaphragm. Molecules of
oxygen and carbon dioxide are passively
exchanged, by diffusion, between the gaseous
external environment and the blood. This
exchange process occurs in the alveoli air sacs in
the lungs.In fish and many invertebrates,
respiration takes place through the gills. Other
animals, such as insects, have respiratory systems
with very simple anatomical features, and in
amphibians even the skin plays a vital role in gas
exchange. Plants also have respiratory systems
but

8. but the directionality of gas exchange can be
opposite to that in animals. The respiratory
system in plants also includes anatomical
features such as holes on the undersides of leaves
known as stomata.

9. Key concept
AIR TRACT INSPIRATION EXPIRATION

10. CELLULAR
RESPIRATION
GLYCOLISIS KREB S CYCLE

11. Respiratory system
Akku and chiku were playing in school
playground .

12. Yes ,when you run
fast you need more
energy.
What is the link
between energy
and breathing.

13. This is a process
known as
respiration..
Do you know how
these process takes
place…

14. No let us study the
process..

15. Respiratory system
Respiratory system is the organs in your body that
helps your body that helps you breath.so you can
deliver oxygen and take away carbondioxide.

16. Parts of respiratory system
 Observe the image and videos given..

17. OBSERVE THE VIDEOS GIVEN
1.a

18. 1.b

19. Wow the
trachea is like
water pipe
And the lungs is
exactly look like the
half of tomato.let
have a look on it

20. Observe the image

21. Parts and functions
 The respiratory system extends from the nostrils to
the lungs.
 Nostrils- The opening through which air enters the
body.There are minute hairs and mucosa in the
nostrils.They prevent the entry of dust and harmful
germs into the lungs.
 Nasal cavity-the chamber following the nostrils.It
opens into the pharynx.
 Epiglottis-The oesophagus and trachea start at the
pharynx ,a common passage for food and air.So there
is a chance for food to enter the trachea.it is the
epiglottis that prevent this.

22.  Trachea-Starts at the pharynx .It is made up of
incomplete rings of cartilage.There are cilia and
mucus in this.
 Bronchi-Two branches of the trachea.Each open
into a lung on each side.
 Lungs-Two lungs found on either side of the heart
in the the thoracic cavity.These are soft
,spongy,and elastic air bag.Lungs are lobular
organs.The right lung has three lobes,the left has
two lobes.

23.  The branching network of bronchi,bronchioles, and alveoli
constitute the lung.
 Pleura-Double membrane covering the lung.There is a fluid
between these membranes.The fluid reduces friction when
the lungs contract and relax.
 Bronchioles-Branches of the bronchi.carry air into the alveoli.
 Alveoli-Each bronchiole ends in a group of alveoli.The lung is
made up of alveoli.There are blood capillaries covering the
alveoli.Exchange of gases takesplace at the alveoli.The alveoli
increase the surface area of the lungs,thus making exchange
of gases efficient.
 Diaphragm-It is the largest muscle of the body.

24. Respiratory system consists of
Nostrils Nasal cavity Pharynx
Trachea Bronchi Bronchioles
Alveoli

25. Mechanism of breathing
 Observe the given diagram and the video

28. The pathway of inspiration
Atmospheric air External nostrils Nasal cavity
Nasopharynx Larynx Trachea
Bronchi Bronchioles Alveolar duct
Alveoli.
The pathway of Expiration.
Alveoli Alveolar ducts Broncioles
Bronchi Trachea Larynx Nasopharynx
Nasal cavity External nostrils Atmospere.

29.  The inflow and out flow of air between atmosphere
and te alveoli of the lungs is called breathing
 It is effected by the expansion and contraction of
lungs.
 During inspiration (inhalation), the diaphragm and
intercostal muscles contract.
 During exhalation, these muscles relax. The
diaphragm domes upwards.
 This results the pulling of the ribs upwards and
outwards.

30. Now on the basis of
indicators given
formulate inferences

31. INDICATORS
 How does the structure of the lungs suit the
process of breathing?
 What change occurs in the thoracic wall during
breathing?
 What are the changes occurring to the air pressure
in the thoracic cavity during the change in the
shape of the diaphragm?

32. Consolidation
 The structure of the lungs is most suitable for the
process of breathing.It is the alveoli of the lungs
that exchange of gases takes place.Since there are
a number of alveoli ,there is an increased surface
area for the lungs.
 Also the muscles between the ribs and the
diaphragm help the process of inspiration and
expiration.
 The changes that occur to the thoracic wall and
the diaphragm help the processes of inspiration
and expiration.

33.  The changes that occur to the thoracic wall and
the diaphragm help the processes of inspiration
and expiration,
 Diaphragm is a muscular wall that separate the
thoracic and abdominal cavities in mammals.
 When the diaphragm lowers , the thoracic cavity
expands and the pressure inside it lowers.Then air
rushes into the lungs(inspiration).

34.  When the diaphragm rises,the thoracic cavity
contracts and the pressure inside it
increases.Then air is pushed out of the
lungs(expiration).
Are the components of
inhaled and exhaled air
is the same…you have
got the answer by
observing the table
given

35. Components Inhaled air in percent Exhaled air in percent
Oxygen 21 14
Carbondioxide 0.03 5
Water vapour 0.03 2.06
Nitrogen 78.94 78.94

36. Consolidation
 The amount of oxygen in the expired air is less than
that in the inspired air.it is because some oxygen in
the inspired air is absorbed into blood.
 The amount of carbondioxide in the expired air is
more .it is because during the exchange of gases ,some
carbondioxide in the blood diffused into the air in the
lungs.
 When energy is produced in the cells,water is formed
as a by-product.a portion of this water joins the
expired air.that is why the amount of water is more in
the expired air.
 Nitrogen is neither absorbed or expelled.so there is no
difference in the amount of nitrogen.

37. Oxygen into the cell
 Observe the video

38. Observe the images

40. Description
 Blood is the medium of transport of respiratory gases
 Blood transport oxygen from the lungs to the different
body tissues.
 Red coloured ,iron containing respiratory pigment
called haemoglobin is present in blood
 After the pulmonary gas exchange, oxygen is
transported to various body tissues through the
blood.
 The blood in the pulmonary artery has less oxygen
and more carbondioxide.
 In the alveolus,the concentration of oxygen is more
than that in the blood within the capillaries.so oxygen
diffuses into the blood from the alveolus.

41.  When the oxygen enters the blood ,the
haemoglobin in blood combines with that oxygen
to form oxyhaemoglobin.
 Haemoglobin combines easily with oxygen.
 Oxyhaemoglobin is an unstable compound,so it
gives up oxygen very easily also.
 There is no nucleus or other cell organelles in the
red blood cells,so they can contain a good amount
of haemoglobin.

42. Cellular respiration
 Observe the structure of mitochondria


43.  A mitochondrion has a covering of two
membranes.
 They are the inner membrane and the outer
membrane.
 The inner membrane has folds called cristae.
 The substance within the inner membrane is
called matrix.
 Krebs cycle takes place in the matrix
 ATP synthesis takes place in the cristae.

44. Observe the illustration of cellular
respiration

46. Description
 The production of energy within the cell is called
cellular respiration.
 Cellular respiration has two stages namely,
 1.glycolysis .2. Krebs cycle .
 In gycolysis glucose molecules breakdown to form
pyruvic acid .
 Glycolisis takesplace in the cytoplasm
 Krebs cycle takes ,place in the mitochondria,oxygen is
needed.

47.  During glycolysis 4 ATP molecules of energy is produced
from a glucose molecule.From this 2ATP is utilized for
the glycolysis reaction and the net amount of energy is
2ATP.
 ATP is adenosine triphosphate and ADP is adenosine
diphosphate.
 Pyruvic acid is formed as a result of glycolysis in the
cytoplasm.
 The pyruvic acid formed in the cytoplasm enters the
mitochondrion

48.  Due to the series of chemical reaction taking place in the
mitochondrion,energy is produced along with the by-products
water and carbondioxide.
 Pyruvic acid Energy + CO2 +Water
 Excess water leaves the body in the form of
urine,sweat,and as water vapour in te exhaled air.these
reactions were discovered by Hans Adolf Krebs .So these
reactions are together known as krebs cycle.

49. The transport of carbondioxide
 Analyse the figure

50. Cell
carbondioxide
formed by cellular
respiration
To the tissue fluid
To the blood
By dissolving in the water of plasma
As bicarbonate by dissolvinginto
the water of the red blood cells
As carbaminohaemoglobin by
combining with haemoglobin

51. To the alveoli in the lungs To the outside
through the nostrils

52. Consolidation
 Carbondioxide is formed in cells during cellular
respiration.
 This carbondioxide reaches the tissue fluid.
 The carbondioxide enters blood from the tissue fluid.
 Carbondioxide dissolves in the water in the blood
plasma forming carbonic acid
 Carbondioxide dissolves in the water in the red blood
cells forming bicarbonate

53.  Carbondioxide combines with haemoglobin to form
carbaminohaemoglobin
 These substance reach the alveoli through blood.
 They turn again into carbondioxide.
 The carbondioxide is exhaled through the nostrils

54. Now I understand
how our
respiratory system
works..thanku
You are welcome..

55. Thanku