Revision of Respiratory systemMechanics-changesGas Exchange- changes

State the muscles involved in the respiratory system.

Diaphragm Intercostal muscles External intercostal muscles Rectus abdominus Sternocleidomastoid Lungs

(Plural cavity) (alveoli) (Bronchus, Bronchiole, trachea,)

Easy way to remember the mechanics of respiration

Muscles, what are they doing, active contraction or relaxation.

Movement – of the ribs and sternum and abdomen.

Thoracic cavity volume, either increase or decrease which causes.

Lung volume to decrease or increase, which causes

Inspiration or expiration

MECHANICS OF BREATHING

REST EXERCISE

INSPIRATION

EXPIRATION

MECHANICS OF BREATHING

REST EXERCISE

INSPIRATION DIAPHRAGMEXTERNAL INTERCOSTALS

INCREASE VOLUME OF THORACIC CAVITY

DECREASE PRESSURE

AIR MOVES IN

EXPIRATION PASSIVE

DIAPHRAGMEXTERNAL INTERCOSTALSDECREASE VOLUME OF THORACIC CAVITY

INCREASE PRESSURE

AIR MOVES OUT

MECHANICS OF BREATHING

REST EXERCISE

INSPIRATION DIAPHRAGMEXTERNAL INTERCOSTALS

INCREASE VOLUME OF THORACIC CAVITY

DECREASE PRESSURE

AIR MOVES IN

DIAPHRAGMEXTERNAL INTERCOSTALS CONTRACT HARDEREXTRA MUSCLES

GTER INCREASE VOLUME OF THORACIC CAVITY

GTER DECREASE PRESSURE

MORE AIR MOVES IN

EXPIRATION PASSIVE

DIAPHRAGMEXTERNAL INTERCOSTALSDECREASE VOLUME OF THORACIC CAVITY

INCREASE PRESSURE

AIR MOVES OUT

INTERNAL INTERCOSTALS CONTRACT

RECTUS ABDOMINUS CONTRACTS

GTER DECREASE VOLUME OF THORACIC CAVITY

GTER INCREASE PRESSURE

MORE AIR MOVES OUT

AB

Exam Question

With reference to the mechanics of breathing describe how the cyclist is able to inspire great amounts of oxygen during the training ride.

[4]

Describe how the mechanics of breathing alter during exercise to expire greater volumes of carbon dioxide.

[4]

A B

Answer

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

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

Describe how the mechanics of breathing ensure carbon dioxide is expired during the training run. [3 marks]

ANSWER

  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

THE RESULT

STERNOCLEIDOMASTOID, SCALENES AND

PECTORALIS MINORIS CONTRACT

DURING INSPIRATION

RECTUS ABDOMINUS CONTRACTS

DURING EXPIRATION

MOST COMMON MISTAKESCandidates often:1. Confuse the role of volume and pressure2. Say the lungs contract!!!!!!!!!!3. Forget to say that MORE air moves in and

out during exercise

State the sites of gas exchange and the gases that can transfer.

IS EITHER:

EXTERNAL = AT THE ALVEOLI

INTERNAL = AT THE MUSCLE CELL

CAN BE EITHER O2 OR CO2

EXERCISE OR REST

What’s it all about?

ALL ABOUT

PARTIAL PRESSUREOF ONE GAS WITHIN AIR

EXTERNAL - OXYGEN - REST

HIGH PPO2 IN ALVEOLILOW PPO2 IN BLOOD

CONCENTRATION GRADIENT

GAS ALWAYS MOVES FROM HIGH TO LOW

EXTERNAL - OXYGEN - EXERCISE

SAME PPO2 IN ALVEOLILOWER PPO2 IN BLOODGTR CONCENTRATION

GRADIENTMORE OXYGEN ENTERS BLOOD

(ii) Explain how the performer is able to exchange greater volumes of oxygen and carbon dioxide between the lungs and the blood during exercise. (4 marks)

4 marks max: 1. Gas flows from area of high pressure/concentration to

low 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 8. Increased surface area of lungs

Have to be in the

answer

Have to be in the

answer

(i) How is oxygen exchange increased at the muscle tissues (gas diffusion) during the training run? Why is this beneficial to performance? (5 marks)

(How exchanged)

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) 7 Delays OBLA/delays fatigue 8 Increased energy production/increased intensity/increased duration

of exercise

Efficient respiration is an important factor for effective performance in sport. Describe in detail the process of gaseous exchange either at site A i: at site B. (4 marks)

  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

How is oxygen transported in the blood to the working muscles? [2 marks]

  Dissolved in plasma Attaches to haemoglobin Forms oxyhaemoglobinb/Hb + 02  

Carbon dioxide is a by-product of aerobic respiration.

(i) Describe how carbon dioxide is transported in the blood. (2 marks)

RCC You will need to identify the controls to the RCC.

RECEPTORS

BAROCHEM

OPROPRI

O

DETECT WHAT?INCREASE

INPRESSURE

INCREASE IN ACIDITY MOVEMENT

WHERE? IN THE BLOOD VESSELS IN THE BLOOD

IN TENDONS AND MUSCLE

FIBRES

REMEMBER THE REVERSE HAPPENS DURING RECOVERY

THE RCC

LOCATED IN THE MEDULLA OBLONGATA RECEIVES MESSAGES FROM THE

RECEPTORS SENDS MESSAGES TO THE RESPIRATORY

MUSCLES TO:

CONTRACT HARDEROR

START CONTRACTING TO ASSIST IN INSPIRATION OR EXPIRATION

INTERCOSTAL NERVE TRANSMITS IMPULSE TO

INTERCOSTAL MUSCLES

PHRENIC NERVE TRANSMITS IMPULSE TO THE

DIAPHRAGM

Explain how the respiratory centre uses neural control to produce changes in the mechanics of breathing. [2 marks]

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

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

Dynamics of Respiratory system 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.

Dynamics of Respiratory system 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

100

80

60

40

20

0rest sw im recovery

tim e (m inutes)

m inuteventila tion(L/m in)

Dynamics of Respiratory system 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)1 2 0

1 0 0

8 0

6 0

4 0

2 0

M in u tev en tila tio n(L /m in )

R es t S w im R ec o v e ry

T IM E (m in u tes)

1

2

3

4

5

6

Dynamics of Respiratory systemDefine minute ventilation and give

an average value during maximal exercise. ( 2 marks)

 Describe tidal volume. Explain

what you would expect to happen to tidal volume during exercise. (2 marks)

 

Define minute ventilation and give an average value during maximal exercise. ( 2 marks)

  (definition) The volume of air inspired or expired in one minute/TVxf=VE

(value) Range 80- 180 L/min

  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]

Dynamics of Respiratory system

CRITICALLY EVALUATE THE EFFECT OF

EXERCISE ON THE RESPIRATORY

SYSTEM

Part e – RESPIRATORY QUESTION

WE MUST CONSIDER:RESPIRATORY MUSCLES

CAPILLARISATION OF ALVEOLI

TIDAL VOLUMES

WE MUST CONSIDER:HEALTH AND

PERFORMANCEASTHMASMOKING

WE MUST CONSIDER:EFFECT ON PERFORMANCEEFFECT ON ASTHMA AND

SMOKING THEIR EFFECT ON

EXERCISE

So critically evaluate

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).

   

  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

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

  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  

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

THE END