Respiration under Unusual Conditions Flashcards
What happens to haemoglobin during exercise
Haemoglobin is fully saturated with Oxygen
What happens to blood gases during exercise
Initial stage and Moderate Exercise
Partial pressure of O2 and CO2 normal
Vigorous exercise
H+ increases (anaerobic metabolism)
What happens to pulmonary ventilation rate during exercise
Increases (hyperventilation)
Changes in ventilation during exercise in the initial, moderate and vigorous stages
Very rapid increase in initial stage, increases (less drastic) in moderate and vigorous exercise
What causes a rapid increase in ventilation in the initial stage of exercise
Attributed to motor centre activity and afferent impulses from proprioceptors of limbs, joints and muscles
Neural control - respiratory centres in brain activated
What causes increases in ventilation during moderate and vigorous exercise
Oxygen demands and CO2 levels increase, chemoreceptors detect this and cause an increase in ventilation
Rise in temperature also might cause increase
Effect of increased blood flow to muscles during exercise
Increased cardiac output and thus increased O2 consumption
What is the effect of the decrease in pH and increase in temperature during exercise
Unloading of O2 from blood into muscle
Effects of altitude on the body
Hypoxia
Loss of Appetite
Changes in mental performance
Insomnia
What causes altitude’s effects on the body
Barometric pressure decreases at altitude compared to sea level
Body is left susceptible to hypoxia, affecting delivery of oxygen to body tissues
What does exposure to hypoxia at altitude cause (in terms of receptors)
Acute hypoxia is detected by peripheral chemoreceptors, which try to increase breathing
This however causes pCO2 to fall and Cerebrospinal Fluid (CSF) to go alkaline
System is trapped
- Breathing more, death from alkalosis
- Not enough oxygen, death
What happens to the blood at a more chronic exposure to high altitude
Oxygen carrying capacity is increased with adaptations like 2,3 DPG and polycythaemia
How is the acid-base imbalance corrected at chronic exposure to altitude
Renal system kicks in to increase removal of bicarbonate ions
Effects of scuba diving on the body (simply)
Body is exposed to significant increase of pressure
At 10m below sea level, 1 atm is from above and 1 atm from weight of surrounding water - 2 atm total
Effects of scuba diving on gases in the body
Hyperoxia - e.g. Oxidative stress
Increase in Nitrogen (Venous gas microbubbles)