Transcript Revision of Respiratory system Mechanics

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Diaphragm
Intercostal muscles
External intercostal muscles
Rectus abdominus
Sternocleidomastoid
Lungs
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(Plural cavity)
(alveoli)
(Bronchus, Bronchiole, trachea,)
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Muscles, what are they doing, active contraction or
relaxation.
Movement – of the ribs and sternum and abdomen.
 Thoracic cavity volume, either increase or decrease
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which causes.
 Lung volume to decrease or increase, which causes
 Inspiration or expiration
REST
INSPIRATION
EXPIRATION
EXERCISE
REST
INSPIRATION
DIAPHRAGM
EXTERNAL INTERCOSTALS
INCREASE VOLUME OF
THORACIC CAVITY
DECREASE PRESSURE
AIR MOVES IN
EXPIRATION
PASSIVE
DIAPHRAGM
EXTERNAL INTERCOSTALS
DECREASE VOLUME OF
THORACIC CAVITY
INCREASE PRESSURE
AIR MOVES OUT
EXERCISE
INSPIRATION
REST
EXERCISE
DIAPHRAGM
EXTERNAL INTERCOSTALS
DIAPHRAGM
EXTERNAL INTERCOSTALS
CONTRACT HARDER
EXTRA MUSCLES
INCREASE VOLUME OF
THORACIC CAVITY
DECREASE PRESSURE
AIR MOVES IN
GTER INCREASE VOLUME OF
THORACIC CAVITY
GTER DECREASE PRESSURE
MORE AIR MOVES IN
EXPIRATION
PASSIVE
DIAPHRAGM
EXTERNAL INTERCOSTALS
DECREASE VOLUME OF
THORACIC CAVITY
INTERNAL INTERCOSTALS
CONTRACT
RECTUS ABDOMINUS
CONTRACTS
INCREASE PRESSURE
GTER DECREASE VOLUME OF
THORACIC CAVITY
AIR MOVES OUT
GTER INCREASE PRESSURE
MORE AIR MOVES OUT
A
B
Describe how the
 With reference to
mechanics of
the mechanics of
breathing alter
breathing describe
during exercise to
how the cyclist is
expire greater
able to inspire great
volumes of carbon
amounts of oxygen
dioxide.
during the training
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ride.
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A
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B
4 marks maximum (inspire)
1External intercostal muscles
contract with more force
2Diaphragm contracts/flattens
3More muscles involved/
pectoralis minor
sternocleidomastoid/scalenes
4 Rib cage lifted further up and
out
5Pressure of thoracic cavity is
decreased
6Volume of thoracic cavity
increased
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1.This process becomes active
2.Due to internal intercostal
contracting
3.Abdominal muscles
contracting
4.Diaphram pushed up
harder/rib cage pulled in and
down
5.Decrease in volume of
thoracic cavity
6.Causing an increased
pressure within thoracic
cavity
ANSWER
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This process becomes active
Due to internal intercostal contracting And abdominal
muscles contracting
 Diaphragm relaxes/pushed up
 Rib cage pulled in and down
 Causing a decrease in volume of thoracic cavity
 Causing an increased pressure within thoracic cavity
 More air pushed out of the lungs
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STERNOCLEIDOMASTOID,
SCALENES AND
PECTORALIS MINORIS
CONTRACT
DURING
INSPIRATION
RECTUS ABDOMINUS
CONTRACTS
DURING
EXPIRATION
Candidates often:
1. Confuse the role of volume and pressure
2. Say the lungs contract!!!!!!!!!!
3. Forget to say that MORE air moves in and out
during exercise
IS EITHER:
EXTERNAL = AT THE ALVEOLI
INTERNAL = AT THE MUSCLE CELL
CAN BE EITHER O2 OR CO2
EXERCISE OR REST
ALL ABOUT
PARTIAL
PRESSURE
OF ONE GAS
WITHIN AIR
EXTERNAL - OXYGEN - REST
HIGH PPO2 IN ALVEOLI
LOW PPO2 IN BLOOD
CONCENTRATION
GRADIENT
GAS ALWAYS MOVES
EXTERNAL - OXYGEN - EXERCISE
FROM HIGH TO LOW
SAME PPO2 IN ALVEOLI
LOWER PPO2 IN BLOOD
GTR CONCENTRATION
GRADIENT
MORE OXYGEN ENTERS BLOOD
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Have to
4 marks max:
the
1. Gas flows from area of high pressure/concentration be
to in
low
answer
pressure/concentration
2. Partial pressure of oxygen (PO2) is higher/increases in the
lungs/alveoli
3. Partial pressure of oxygen (PO2) is lower/decreases in the
blood
4. Partial pressure of carbon dioxide (PCO2) is lower/decreases in
the lungs/alveoli
5. Partial pressure of carbon dioxide (PCO2) is higher/increases
in the blood
6. During exercise there is a greater pressure gradient for
oxygen/ carbon dioxide/increased diffusion gradient
7. Increased blood flow to the lungs
Have to be in
8. Increased surface area of lungs
the answer
(How exchanged)
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1 High partial pressure of oxygen (PO2) in blood
2 Lower/decreased PO2 in muscle (cell)
3 Increased diffusion/concentration gradient
4 Increase in temperature allows increased release of oxygen from
haemoglobin/increased dissociation of oxygen
5 Bohr Effect/increase in acidity/increased CO2/carbonic acid/lactic
acid/lower pH of blood allows greater release of oxygen from
haemoglobin
6 Myoglobin is used to transport/store more oxygen (to mitochondria)
(Why beneficial) (2 marks sub max)
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Delays OBLA/delays fatigue
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Increased energy production/increased intensity/increased duration
of exercise
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At site A (Lungs)
external respiration/alveolar-capillary membrane/exchange of gases between air
and blood/via diffusion
the movement (through a semi-permeable membrane) from areas of high
pressure to areas of low pressure
the partial pressure of the oxygen in the blood is less than that in the alveoli
oxygen travels from the alveoli to the blood
carbon dioxide travels from the blood to the alveoli
the partial pressure of carbon dioxide in the blood is greater than that in the
alveoli
OR
At site B (Tissues)
internal respiration/tissue-capillary membrane/exchange of gases between blood
and tissues/via diffusion
the movement (through a semi-permeable membrane) from areas of high
pressure to areas of low pressure
oxygen travels from the blood to the tissues
the partial pressure of oxygen in the blood is greater than that in the tissues
carbon dioxide travels from the tissues to the blood
the partial pressure of carbon dioxide in the blood is less than that in the tissues
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Dissolved in plasma
Attaches to haemoglobin
Forms oxyhaemoglobinb/Hb + 02
BARO
PROPRI
CHEMO
O
DETECT WHAT?
INCREASE
IN
PRESSURE
INCREASE IN
ACIDITY
MOVEMENT
WHERE?
IN THE BLOOD
VESSELS
IN THE BLOOD
IN TENDONS AND
MUSCLE FIBRES
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LOCATED IN THE MEDULLA OBLONGATA
RECEIVES MESSAGES FROM THE
RECEPTORS
SENDS MESSAGES TO THE RESPIRATORY
MUSCLES TO:
CONTRACT HARDER
OR
START CONTRACTING TO ASSIST
IN INSPIRATION OR EXPIRATION
INTERCOSTAL NERVE TRANSMITS
IMPULSE TO
INTERCOSTAL MUSCLES
PHRENIC NERVE TRANSMITS
IMPULSE TO THE
DIAPHRAGM
RCC stimulated by (submax 1):
Prorioceptors detect movement
Baroreceptors monitor (blood) pressure! lung stretch receptors
Chemoreceptors detect changes in pH, blood chemistry!oxygen
tension
 Thermoreceptors detect changes in temperature
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RCC responds by:
Regulated by inspiratory!expiratory centres
Which sends nerve impulses (via phrenic/intercostals nerves)
To the respiratory muscles
Increased rate and depth of breathing
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Graph and chart questions. First thing to do is not panic.
Read the question (RTFQ) Ensure that you know what it
wants you to interpret.
If it wants you to draw chart then ensure that you add the
values on the axis.
Lets look at a few.
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Minute ventilation is defined as the volume of air inspired or expired in one
minute. (4 marks)
Sketch a graph below to show the minute ventilation of a swimmer completing a
20-minute submaximal swim. Show minute ventilation: prior to the swim, during
the swim, for a ten minute recovery period.
[4]
120
minute
ventilation
100
(L/min)
80
60
40
20
0
rest
swim
time (minutes)
recovery
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Prior
1.
Starting value below 20 L/min
2.
Anticipatory rise prior to exercise
During
3.
Rapid rise (60-120L/min)
4.
Slower rise/plateau (60-120L/min)
Recovery
5.
Rapid decrease at end of exercise
6.
Slower decrease towards resting value
(Refer to diagram)
120
4
100
80
Minute
ventilation
(L/min)
5
3
60
40
20
6
2
1
Rest
Swim
TIME (minutes)
Recovery
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Define minute ventilation and give an
average value during maximal exercise.
( 2 marks)
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Describe tidal volume. Explain what you
would expect to happen to tidal volume
during exercise. (2 marks)
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Define minute ventilation and give an average value during
maximal exercise.
( 2 marks)
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(definition)
The volume of air inspired or expired in one minute/TVxf=VE
(value)
 Range 80- 180 L/min
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Describe tidal volume. Explain what you would expect to
happen to tidal volume during exercise. (2 marks)
Description
The volume of air inspired p expired per breath [1]
It would increase [1]
WE
MUST
CONSIDER:
CRITICALLY
EVALUATE
WE
MUST
CONSIDER:
WE
MUST
CONSIDER:
EFFECT
ON
PERFORMANCE
RESPIRATORY
MUSCLES
THE
EFFECT
OF
HEALTH
AND
EFFECT
ON
ASTHMA
AND
CAPILLARISATION
OF
EXERCISE
ON
THE
PERFORMANCE
SMOKING
ALVEOLI
RESPIRATORY
ASTHMA
THEIR
EFFECT
ON
TIDAL
VOLUMES
SYSTEM
SMOKING
EXERCISE
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Evaluate critically the impact of different
types of physical activity on the respiratory
system with reference to lifelong
involvement in an active lifestyle (to
include an awareness of asthma and
smoking).
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Respiratory Structures- External Respiration
increased surface area of alveoli
increased elasticity of lungs
increased capillary density around alveoli
greater amount of O2 diffused in to blood
greater amount of CO2 diffused in to alveoli
greater gaseous exchange/ increase
pulmonary diffusion
greater saturation of haemoglobin with
oxygen
Respiratory Structures- Internal Respiration
increased capillary density around muscle
tissue
greater amount of O2 diffused in to muscle
cell
greater amount of CO2 diffused in to blood
greater gaseous exchange/ increased muscle
and tissue diffusion
increased a-VO2 difference
increased a-VCO2 difference
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Improvements to Breathing
Mechanisms
strengthens respiratory muscles/
respiratory muscle hypertrophy
diaphragm, intercostals, SCM, scalenes,
abdominals
increased efficiency of the mechanics of
breathing
increased depth of breathing
decreased breath frequency
reduces or delays respiratory muscle
fatigue
Increases in Lung Volumes or Capacities
increased tidal volume during maximal
exercise
increased vital capacity
decreased residual volume
increased inspiratory reserve volume
increased expiratory reserve volume
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These physiological adaptations would result in:
increased VO2 max
delays OBLA or lactate threshold/ increases
endurance capabilities
lifelong involvement in physical activity
Altitude Training
reduced ppO2 / hypoxic conditions
initial decrease in the efficiency of the respiratory
system
BUT increase in efficiency of respiratory system when
returning to sea level
Reference to any relevant physiological response e.g
increased capillary density.
Choice to live high or use hypoxic tents but train low
Asthma
aerobic training can trigger EIA
particularly in cold / dry conditions
asthma can inhibit people from taking part in aerobic
training
Inspiratory muscle training (IMT) or aerobic training
can alleviate symptoms of asthma
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Smoking
decreases the efficiency of the respiratory
system / decreases respiratory health
decreases the efficiency to supply O2 to
muscles
carbon monoxide reduces the amount of O2
absorbed in blood/
Hb has greater affinity to CO than O2
decreased gaseous exchange or diffusion
gradient
increases likelihood of respiratory diseases
(e.g. shortness of breath/ coughing/ lung
cancer/ emphysema etc.)
damage to respiratory structures
tar coats the airways and inhibits gaseous
exchange/tar builds up in lungs
impairs lung function
narrowing of air passages causing increase in
respiratory resistance
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THE END