Copy of Breathing and Respiration (1).pptx

Breathing and Respiration.

1. Breathing and Respiration

2. Respiration Cellular respiration is the process by which cells use oxygen to break down sugar and obtain energy.   2

3. Breathing and Respiration- the Difference Respiration Chemical process Carry oxygen to cells, get rid of carbon dioxide and release energy Breathing Mechanical Process Process where air is taken into and expelled out of the body 3 Carbon dioxide is toxic to the body. So to get rid of it the body expels it during respiration to bring in fresh oxygen to the cells. During exercise, the body runs out of things quicker and produces carbon dioxide much faster. To keep up with expelling this harmful waste, the body naturally blows off this excess by increasing the speed at which it is expelled. The rate at which oxygen circulates also increases during the time of increased demand.

4. Respiration takes place in all our cells all the time Our cells contain tiny structures called mitochondria. This is where energy is released from glucose. Muscle cells use up lots of energy. They have lots of mitochondria. Living things transfer chemical energy from the food they eat and release it to do work during respiration. 4

5. Working your muscles Transporting chemicals Absorbing food (active transport) Sending messages along nerves Building cells for growth Keeping your body temperature constant 5 Using Energy

6. Activity! Step 1: Breathe in and out normally Have a partner record your no. of breaths per minute Step 2: Jog in place for 60s and stop Have your partner record your no. of breaths per minute. 6

7. Analysis What effect does exercise have on breathing rate? Explain the results Explain the role of respiration in this activity. Why does breathing rate increase after exercise? - Oxygen to cells faster in times of exertion - Demand of oxygen and release of energy 7

8. Types of Respiration Two types: Aerobic and Anaerobic Respiration Aerobic respiration is the process of producing cellular energy involving oxygen and mostly takes place in mitochondria glucose + oxygen → carbon dioxide + water C 6 H 12 O 6  + 6O 2  → 6CO 2  + 6H 2 O Unlike aerobic respiration, anaerobic respiration does not need oxygen. It is the release of a relatively small amount of energy in cells by the breakdown of food substances in the absence of oxygen 8

9. Anaerobic Respiration 9 Anaerobic respiration happens in muscles during hard exercise: glucose → lactic acid Glucose is not completely broken down, so much less energy is released than during aerobic respiration. There is a build-up of  lactic acid  in the muscles during vigorous exercise. Anaerobic respiration also happens in plant cells and some  microorganisms (eg. Yeast). Anaerobic respiration in yeast is called fermentation and is used during brewing and bread-making: glucose → ethanol + carbon dioxide C 6 H 12 O 6  → 2C 2 H 5 OH + 2C0 2

10. Anaerobic Respiration 10 Ethanol is the alcohol found in alcoholic drinks like beer and wine. In bread-making, bubbles of carbon dioxide gas expand the dough and help the bread rise.

11. Difference between Aerobic and Anaerobic Respiration 11 Aerobic Anaerobic Oxygen Needed Not needed Glucose Breakdown Complete Incomplete End Product(s) Carbon dioxide and Water Animal cells: lactic acid Plant and yeast: Carbon dioxide and Ethanol Energy Released Relatively large amount (16 times more than anaerobic) Relatively small amount

12. Gaseous Composition of Air 12

13. Percentage of Gases Inspired and Expired 13 Gas Inspired Air (Breathing in) Expired Air (Breathing out) Oxygen 21% 16% Carbon dioxide 0.04% 4% Nitrogen 78% 78% Water Vapour Variable Saturated

14. Human Respiratory System 14

15. Ventilation Before air enters and reaches our lungs through nose and mouth, the air is warmed, moistened, filtered and cleaned because otherwise, it might damage our lungs. The cells lining the nose and trachea make slimy mucus. Dust and germs get trapped in the slime. The cells have tiny hairs or cilia on them. These beat to carry the mucus up to your nose and throat, until you cough or snort it out 15

16. Ventillation 16 Breathing in Breathing out the internal  intercostal muscles  relax and the external intercostal muscles contract, pulling the ribcage upwards and outwards the external intercostal muscles relax and the internal intercostal muscles contract, pulling the ribcage downwards and inwards the  diaphragm  contracts, pulling downwards the diaphragm relaxes, moving back upwards l ung volume increases and the air pressure inside decreases lung volume decreases and the air pressure inside increases air is pushed into the lungs air is pushed out of the lungs

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18. Human Thorax The  trachea  branches into two  bronchi  (one to each lung).  Pleural membranes  surround each lung.  Cartilage rings  in the walls of the trachea help to keep it open. The bronchi split into smaller and smaller tubes called  bronchioles . These end in microscopic air sacs called  alveoli . There is a muscular  diaphragm  below the lungs. 18

19. Gas Exchange Gas exchange  in the lungs happens in the  alveoli . Some of the features of alveoli include: thin walls (just one cell thick) large surface area moist surface many blood capillaries 19

20. Did You Know? Limewater  turns milky in the presence of carbon dioxide, so it can be used to show the differences between inhaled (inspired) air and exhaled (expired) air. The limewater immediately turns milky on contact with exhaled air. 20

21. Tidal Volume and Vital Capacity Tidal volume  (TV) is the  volume  of air moved into and out of the lungs with normal quiet breathing. The tidal   volume  of a normal healthy person is about 500ml.  Vital capacity  is the total of maximum  volume  that can be inhaled and exhaled during a single breath. 21

22. Oxygen Debt A temporary oxygen shortage in the body tissues arising from exercise, is known as oxygen debt . Repaying this oxygen debt is vital as lactic acid is toxic and a build up in our cells and muscles can lead to harmful effects if not converted to Carbon dioxide and water quickly enough. The existence of an oxygen debt explains why we continue to breathe deeply and quickly for a while after exercise. 22

23. Smoking Damage to the respiratory system from tobacco is slow and progressive The respiratory system will continuously cleanse itself with mucus, trapping dirt and microbes and then tiny hairs in the system known as cilia ,  sweeping them toward the mouth where the mucus is eventually eliminated.  Smoking damages the cleansing system. 23

24. Consequence of Smoking Many Diseases are associated with smoking. Such as: Bronchitis: Air passage becomes inflamed as the cilia lining the air passage stops beating. Dust and bacteria get trapped in the mucus, forming phlegm which the affected person tries coughing out. This leads to chronic bronchitis. Emphysema: occur when chemicals in tobacco weaken the walls of the alveoli, which leads to breathlessness. Alveoli of an affected individual has a reduced surface area than usual, causing decreased and inefficient gas exchange. 24

25. Consequence of Smoking 25

26. Consequence of Smoking Lung Cancer: Tar is thought to be carcinogenic which leads to lung cancer. Cancer can also originate in the mouth, throat and oesophagus 26

27. Thanks! 👍 27