The Respiratory System Flashcards
What is TV
The amount of air breathed in and out per breath
What is breathing frequency
How many breaths taken per minute
What is minute ventilation
The amount of air breathed in and out per minute
What is the resting volume of tidal volume
500ml
What is the resting volume for breathing frequency
12bpm
What is the resting volume of minute ventilation
6-10L/m
What is the maximal volume of TV
3L
What is the maximal value for breathing frequency
70-120bpm
What is the maximal value of minute ventilation
180L/m
Is inspiration during rest active or passive
Active
What muscles contract during inspiration
Diaphragm
External intercostals
Is expiration during rest and active or passive action
Passive
What additional muscles help inspiration during excercise
Pectorals
SCMs
Trapezius
How does the chest cavity volume and air pressure values differ to rest
Values are greater than those at rest
Why does the chest cavity expand
To create a low area of pressure so air can flow in as particles move from a high to low pressure
Is expiration during excercise active or passive
Active
What additional muscles help expiration during exercise
Inter - intercostals
Abdominals force diaphragm to contract quicker
Describe how vascular shunt takes place
A receptor detects a change
Sends impulse to vasomotor centre
Sympathetic nervous system vasolidates arteries carrying blood to working muscles
Vasoconstriction of arteries carrying blood to non working muscles
Explain the changes to stroke volume during sub maximal excercise
Increase Venus return , Increase SV
SV reaches maximal levels during sub maximal exercise
120-200 ml
SV may decrease as diastole does not have enough time to occur
What is the average value of cardiac output during maximal exercise
20-40L
Describe how the conduction system of the heart controls the systolic phase of the cardiac cycle
SA node generates cardiac impulse
Atrial systole occurs
Impulse travels to AV node
Impulse continues down bundle of His
Causing ventricular contraction
Describe intrinsic control of the heart during exercise
Increase in venous return
RA stretches
SA node increases rate of firing
Increasing end diastolic volume
Explain why more oxygen disassociates from blood into the muscle cell during exercise
Body temperature increases so HG affinity to 02 increases
HG becomes fully saturated during excercise
Working muscles utilise more 02
HG gives up 02 to the muscle easier
Increased 02 diffusion gradient
Increased removal of co2
Name the 5 mechanisms of venous return
Pocket valves
Muscle pump
Respiratory pump
Smooth muscle
gravity
Explain how an increase of Venus return during exercise affects the quality of an athletes performance
Increased VR causes atria to stretch
Stimulating SA node
Increasing HR
Increases SV
Cardiac output increases
Increased performance
Describe the mechanics of breathing for inspiration at rest
EICs contract
Diaphragm contract
Ribs go up and out
Increasing TC volume
Creating an area of low pressure
Explain the role of the SCM muscle during excercise
SCM contracts during respiration
Causes rib cage to move up and out
During expiration SCM relax
Causing rib cage to move down and in
Describe the mechanics of breathing for inspiration during excercise
EICs contact with greater force
Diaphragm contracts with greater force
Additional muscles such as the trapezius are recruited
Chest cavity is greater than at rest
So more air enters lungs as air moves from a low to high pressure
Describe the short term effects of excercise on gas exchange at the alveoli
Gases diffuse from an are of high to low concentration
Therefore more oxygen diffuses from alveoli to blood
Outline how oxygen is transported in blood
Oxygen combines with HG
Oxygen dissolved in plasma
Describe the process of oxygen diffusion at the alveoli during exercise
02 moves from alveoli to blood
High pp of 02 in alveoli
During exercise muscles use more 02
So there is lower pp of 02 in blood
