RESPIRATION FORM 3 2023 CHAPTER 2_F3.pptx

SCIENCE

1. Chapter 2 Respiration

2. Human Respiratory System The breathing organs include the nostrils, nasal cavity, pharynx, larynx, the breathing tract (trachea, bronchi and bronchioles), alveolus, and lungs. Each alveolus has a very thin wall which is one-cell thick, moist and contains a large network of blood capillaries.

3. The Human Respiratory System

4. STRUKTUR PEPARU MANUSIA BRONCHUS BRONCHIOLE ALVEOLUS ALVEOLUS BLOOD CAPILLARY

5. Organs of the respiratory system Function Diaphragm Changes the air pressure in the thoracic cavity by increasing or decreasing the thoracic volume Ribs Protect the lungs Alveolus The place where the exchange of gaseous occurs

6. Organs of the respiratory system Function Intercostal muscles Raise and lower the rib cage during breathing Blood capillaries Carry oxygenated blood from the alveoli and deoxygenated blood to the alveoli

7. The pathway of air in the breathing mechanism Nostril Nasal cavity Pharynx Larynx Trachea Bronchus Bronchiole Alveolus Blood capillaries

8. Inhalation Air is forced into the lungs external intercostal muscle contract internal intercostal muscle relax ribs raised upwards and outwards Diaphragm contract and flatten thoracic volume increases air pressure in the lungs decreases Breathing Mechanism

9. Exhalation Air is forced out of the lungs external intercostal muscle relax Internal intercostal muscle contract rib cage moves downwards and inwards Diaphragm contract and curves upwards thoracic volume decreases air pressure in the lungs increases Breathing Mechanism

10. Inhalation Part that involves Exhalation Contract External intercostal muscles Relax Relax Internal intercostal muscles Contract Upwards and outwards Movement of rib cage Downwards and inwards Contract Diaphragm muscles Relax Flattens Shape of diaphragm Curves upwards Differences between the mechanisms of inhalation and exhalation

11. Inhalation Part that involves Exhalation Increases Thoracic volume Decreases Low Air pressure inside thoracic High Air from atmosphere is forced into the lungs Air movement Air is forced out of the lungs

12. Glass tube- Trachea Y shaped glass tube - Bronchus Ballon – Lungs Glass jar– rib cage Rubber sheet- Diaphragm Air space inside glass jar– Thoracic cavity Model of the lungs

13. The handle is pulled down: volume of bell jar increases Balloon expands Air pressure in bell jar decreases air enters to the balloons through the glass tube The rubber sheet is pushed up: volume of bell jar decreases balloons contracts air pressure inside bell jar increases air is force out from the balloons through glass tube Inhalation Exhalation

14. Percentage of Oxygen in Inhaled and Exhaled air

15. Gaseous Exchange in Human Body Oxygen gas diffuses into the blood capillaries to be transported to all the body cells due to the high concentration of oxygen in the alveoli and low concentration of oxygen in the bloodstream. In the blood, oxygen will combine with haemoglobin in the red blood cells to form oxyhaemoglobin to be transported to the body cells

16. Blood contain high concentration of oxygen and low concentration of carbon dioxide Blood contain low concentration of oxygen and high concentration of carbon dioxide

17. Gaseous exchanges across the alveolus and blood capillary in the lungs

18. Transport of Oxygen Takes place through diffusion Oxygen breathed into the lungs is initially dissolves in the moist layer of the alveoli and then diffuse into the blood capillary. The oxygen combines with hemoglobin in the red blood cells to form oxyhaemoglobin . Oxygenated blood is then sent to all parts of the body through the circulation system of the blood.

19. When the blood reaches the target tissue, the oxygen (released from the red blood cells) diffuses into the tissue cells because of its low oxygen concentration. The deoxygenate blood flows back to the heart and is then pumped to the lungs to be oxygenated again.

20. Adaptation of the alveoli for efficient gas exchange 1. Large surface area 2. Very thin walls 3. Moist inner surface 4. Surrounded by a network of blood capillaries

21. Adaptation of the alveoli Millions of alveoli – to provide a very large surface area for gaseous exchange. A layer of moisture on the inner surface of the alveolus Thin epithelium that is one-cell thick to allow rapid diffusion of gases to and from the alveoli. A network of capillaries surrounds the outer surface of the alveoli

22. Harmful Effects of pollutant on the Respiratory Tract Pollutant Tobacco tar Carbon monoxide Sulphur dioxide Nitrogen dioxide Haze, dust, pollen grain

23. Chemical Substances Harmful effect on the respiratory system Nicotine Causes illnesses like bronchitis, throat cancer and lung cancer Tobacco tar - Blackens the lungs - Lung cancer - kills cells in the air passages and the lungs - increases production of mucus and phlegm in the lungs The Important of A Healthy Respiratory System

24. Chemical Substances Harmful effect on the respiratory system Carcinogen Stimulates the growth of cancer cells, causing lung cancer and throat cancer Sulphur dioxide and nitrogen dioxide Damages the breathing channel and lungs Carbon monoxide - prevents haemoglobin from transporting oxygen around the body - causes a lack of oxygen in our body which may lead to headaches, brain damage or even death

25. Chemical Substances Harmful effect on the respiratory system Forest fire and open burning (Haze) Irritates the respiratory system, causing respiratory disorders such as asthma Burning plastic material (Hydrogen chloride, ammonia and hydrogen cyanide) Corrodes the breathing channel

26. Emphysema Caused by cigarette smoke which causes the alveolus of the lungs to enlarge and be destroy Diseases of the Respiratory System:

27. Bronchitis is caused by irritable substances present in cigarette smoke which causes the alveolus of the lungs to enlarge and be destroyed

28. Lung cancer caused by carcinogenic substances in the cigarette takes place when the lung cells produce tumours .

29. Asthma is caused by the inflammation of the breathing channel breathing channel suddenly becomes narrow causing difficulty in breathing very sensitive to certain allergens Symptom : shortness of breath, wheezing, excessive coughing

30. WAYS TO IMPROVE AIR QUALITY Air filter system Stop smoking Use unleaded petrol Use Catalytic converter Car pooling Electrostatic catalytic Use public transport

31. The Effect of Smoking on the Human Respiratory

32. Adaptation of Organisms in the Respiratory System

33. Moist outer skin (Amphibians) Characteristics : Moist, thin & very permeable to gas

34. Gills (Fish) Each gill composed of : 1) filaments 2) gill arch 3) lamellae

35. Trachea (Insect) Consists of 1) tracheae (air tubes), tracheoles 2) spiracles (the opening structures) 3) air sacs Many tracheoles with thin and moist walls

36. Gaseous Exchange in Plants

37. High concentration Low concentration High concentration Low concentration

38. Stomata and Guard Cell

39. guard cells – control the size of the stoma for gaseous exchange.

40. Parts of a leaf Structure Function Guard cells A pair of epidermal cells that are bean-shaped Surround a stoma Contain chloroplasts Control the size of the stomata Carry out photosynthesis

41. Parts of a leaf Structure Function Stoma Tiny opening at the lower epidermis surrounded by guard cells Allows gaseous exchange (diffusion of carbon dioxide and oxygen) between air spaces in the spongy mesophyll cells and the surrounding atmosphere.

42. The Effect of Osmosis on Stoma Osmosis is the process of water molecules diffuse from the region of low concentration of solution to a region of high concentration of solution through semi-permeable membrane

43. Stoma open during the day to carry out photosynthesis Stoma close at night because the guard cells become flaccid (no photosynthesis)

44. The Effect of Acidic Gases to the Plant