Wrong Answers Flashcards
Identity the three mechanisms of venous return
Smooth muscles
Pocket valves
Muscle pump
Identity the three mechanisms of venous return
Smooth muscles
Pocket valves
Muscle pump
Explain why more oxygen dissociates from the blood into the muscle cell during exercise
Oxygen moves from a high pp to a low pp
During exercise muscles use more oxygen
So more 02 dissasociates from HG
As there is a lower pp of 02 in the muscles
Increasing diffusion gradient
Describe the effects of high altitude exposure on performance in aerobic and anaerobic activities
Decreased pp of 02 in air
Decreased aerobic capacity
Increased breathing frequency
Leading to a decrease in aerobic performance
But increase in aerobic performance
What is meant by cardiovascular drift
Reduced plasma volume, increasing blood viscosity.
Decreasing SV, leading to increased HR to maintain cardiac output
What is an isotonic contraction
Muscle length changes while tension remains constant
Explain hormonal regulation of the heart during excercise
Hormonal regulation controlled by ANS
adrenal gland secretes adrenaline into blood
Excites SA node
Increasing rate of firing
And increases force of muscular contraction
Increasing HR and SV
Describe how the conduction system of the heart controls the systolic phase of the cardiac cycle
Sa node generates own impulse
Atrial systole occurs
Impulse travels to AV node
Down bundle of purjinke and his fibres
Ventriclular stystole occurs
Explain how the redistribution of blood during physical activity occurs
VCC sends messages about where blood is needed
More blood goes to working muscles
Vessels carrying blood to working muscles vasolidate
Vessels carrying blood to non working vasoconstrict
Describe the mechanics of breathing for inspiration at rest
Active process
EICs contract
Diagram contracts
Moving rib cage up and out
Increasing thortic cavity
Creating an area of low pressured so air rushes in
