CTB5 Flashcards
What does the cardiopulmonary system include?
The heart and lungs working together to deliver oxygen and remove carbon dioxide.
How does the autonomic nervous system control the heart?
The sympathetic nervous system increases heart rate and contractility, while the parasympathetic system decreases them.
What is the role of the sinoatrial (SA) node?
The SA node generates the heart’s rhythm, acting as the natural pacemaker.
How is breathing controlled at rest?
Breathing is regulated by the medulla oblongata through signals to the diaphragm and intercostal muscles.
What is respiratory sinus arrhythmia?
A physiological variation in heart rate during breathing; heart rate increases during inspiration and decreases during expiration.
How does exercise affect the cardiopulmonary system?
Exercise increases heart rate, stroke volume, ventilation rate, and oxygen delivery to tissues.
What is VO2 max?
The maximum rate of oxygen consumption during exercise, reflecting aerobic fitness.
How does the cardiovascular system respond to acute exercise?
Increased cardiac output, redistribution of blood to active muscles, and vasodilation in peripheral vessels.
What is stroke volume?
The volume of blood ejected from the left ventricle during each heartbeat.
How does training improve stroke volume?
Cardiac hypertrophy and increased contractility result from endurance training.
What is tidal volume?
The amount of air inhaled or exhaled in a normal breath.
How does ventilation increase during exercise?
Both tidal volume and respiratory rate increase to meet oxygen demands.
What are the long-term effects of regular exercise on the heart?
Increased cardiac efficiency, ventricular hypertrophy, and improved stroke volume.
How does chronic exercise impact the lungs?
Enhanced respiratory muscle strength and improved alveolar ventilation.
What is the role of baroreceptors in blood pressure regulation?
Baroreceptors detect changes in blood pressure and adjust heart rate and vessel tone accordingly.
What is the ventilatory threshold?
The point during exercise where ventilation increases disproportionately to oxygen consumption due to lactic acid accumulation.
How does exercise improve arterial compliance?
Regular exercise reduces arterial stiffness, improving blood flow and pressure regulation.
What happens to oxygen delivery during exercise?
Oxygen delivery increases through higher cardiac output and improved oxygen extraction by tissues.
How does exercise affect blood flow distribution?
Blood is redistributed away from non-essential organs to working muscles.
What is pulmonary ventilation?
The total volume of air moved in and out of the lungs per minute.
What is alveolar ventilation?
The volume of air reaching the alveoli, where gas exchange occurs.
How is lung function assessed clinically?
Through spirometry, measuring parameters like FEV1, FVC, and peak expiratory flow.
What is the FEV1/FVC ratio?
A measure used to diagnose obstructive lung diseases like COPD.
How does exercise increase oxygen extraction by muscles?
Through improved capillary density, mitochondrial function, and haemoglobin affinity adjustments.
What is the Bohr effect?
A decrease in haemoglobin’s oxygen-binding affinity in response to increased carbon dioxide and hydrogen ion concentrations.
How does lactic acid influence ventilation during exercise?
Lactic acid accumulation stimulates ventilation to expel excess carbon dioxide.
What is the significance of measuring cardiac output during exercise?
It indicates the heart’s ability to meet metabolic demands.
How is cardiac output calculated?
Cardiac output = Stroke volume × Heart rate.
How does the phrenic nerve control breathing?
It sends signals from the medulla to the diaphragm to regulate contraction.
What is the oxygen-hemoglobin dissociation curve?
A graph showing the relationship between oxygen saturation and partial pressure of oxygen.
How does chronic exercise improve mitochondrial function?
It enhances the capacity for oxidative phosphorylation and ATP production.
What are the effects of hypoxia on cardiopulmonary function?
Hypoxia increases ventilation and cardiac output to compensate for reduced oxygen availability.
What is the role of chemoreceptors in respiratory control?
Chemoreceptors detect changes in CO2, O2, and pH levels, adjusting breathing accordingly.
How is anaerobic threshold defined?
The point at which the body begins to rely on anaerobic metabolism during exercise.
What is the relationship between ventilation and heart rate during exercise?
Both increase proportionally to oxygen demand and carbon dioxide production.
How does training affect maximal oxygen uptake (VO2 max)?
Training increases VO2 max by improving cardiac output and oxygen extraction efficiency.
How does exercise training reduce resting heart rate?
Increased stroke volume and vagal tone lower the heart rate at rest.
How does pulmonary function adapt to exercise in disease states?
Pulmonary rehabilitation improves ventilation and oxygen exchange in patients with conditions like COPD.
What is the role of bicarbonate in buffering lactic acid?
Bicarbonate neutralises excess hydrogen ions, maintaining blood pH during high-intensity exercise.
How does exercise influence blood pressure regulation?
Exercise improves endothelial function, reducing vascular resistance and systolic pressure.
What is ventilatory efficiency?
The ratio of ventilation to oxygen uptake, indicating the respiratory system’s effectiveness.
What is the significance of respiratory exchange ratio (RER)?
RER indicates the predominant fuel source during exercise (carbohydrates vs. fats).
How does exercise affect ventilation-perfusion matching?
Improved ventilation-perfusion matching enhances oxygen exchange during activity
What happens to arterial oxygen levels during moderate exercise?
Arterial oxygen levels remain constant due to efficient ventilation and gas exchange.
How does hyperventilation impact carbon dioxide levels?
Hyperventilation reduces CO2 levels, potentially leading to respiratory alkalosis.
What adaptations occur in the diaphragm with chronic exercise?
Increased strength and endurance improve ventilation efficiency.
What is oxygen debt?
The extra oxygen consumed post-exercise to restore physiological balance.
How does training improve capillary density in muscles?
It increases capillary networks, enhancing oxygen delivery and waste removal.
What role does adrenaline play during exercise?
Adrenaline increases heart rate, cardiac output, and bronchodilation.
How is exercise capacity assessed clinically?
Through tests like VO2 max measurements and cardiopulmonary exercise testing (CPET).
