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
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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.
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5. - Working your muscles
- Transporting chemicals
- Absorbing food (active transport)
- Sending messages along nerves
- Building cells for growth
- Keeping your body temperature constant
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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.
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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
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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
C6H12O6 + 6O2 → 6CO2 + 6H2O
● 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
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9. Anaerobic Respiration
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◍ 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
C6H12O6 → 2C2H5OH + 2C02
10. Anaerobic Respiration
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◍ 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
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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
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
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16. Ventillation
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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
lung 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
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.
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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
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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.
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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.
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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.
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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.
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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.
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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
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