SSEH2260 mid sem 2

What are the components of ATP?

ATP is made of adenine, ribose, and triphosphate.

What happens when the terminal phosphate in ATP is cleaved?

Energy is released through hydrolysis, releasing 7.3 kcal/mol.

How is ATP constantly remade in the body?

ATP is phosphorylated using energy from food.

What is the role of phosphocreatine in energy production?

Phosphocreatine provides immediate energy by phosphorylating ATP during maximal exercise.

What percentage of energy from carbohydrates is used during high intensity exercise?

During high intensity exercise, carbohydrates supply 80% of energy.

What does glycolysis produce from glucose?

The entire oxidation of glucose produces 32-33 ATP.

How many ATP are produced in anaerobic glycolysis?

2-3 net ATP are produced in anaerobic glycolysis.

What is the role of phosphofructokinase (PFK) in glycolysis?

PFK is the rate limiting enzyme in glycolysis.

Where does glycolysis occur?

Glycolysis occurs in the cytoplasm of the cell.

What is the function of lactic acid during exercise?

H ions from lactic acid can continue to the ETC to produce ATP.

What physical tests can evaluate the anaerobic glycolytic energy system?

Measurement of blood lactate following exercise and muscle biopsies measuring glycogen.

What happens to pyruvate in aerobic glycolysis?

Pyruvate from stage one enters the citric acid cycle.

What is the main purpose of stage 2 in aerobic glycolysis?

The main purpose is to generate H atoms for transfer to the ETC to produce ATP indirectly.

How many pairs of hydrogen are generated from two pyruvate molecules in the citric acid cycle?

A total of 10 pairs of hydrogen are generated from two pyruvate.

How does oxygen influence fatty acid transport?

Oxygen must be available for beta oxidation to proceed.

What is the main fuel source during prolonged moderate intensity exercise?

Stored fats are a plentiful source of potential energy.

What hormones assist in mobilizing fatty acids from adipose tissue?

Adrenaline, noradrenaline, growth hormone, and glucagon.

How much ATP is produced from glycerol after breakdown?

The complete breakdown of a single glycerol molecule synthesizes a total of 19 ATP.

What happens to fatty acids during exercise?

Fatty acids become free fatty acids and enter beta oxidation.

Why is protein not a major fuel source during exercise?

It represents only 2-5% of the fuel utilized during prolonged moderate intensity exercise.

What is deamination in protein metabolism?

Deamination is the removal of the amino group from an amino acid.

How are some deaminated amino acids used for energy?

Some can be converted to pyruvate or Acetyl-CoA, or to CAC substrates.

What is the lactate threshold?

The point where blood lactate increases by 1 mM above resting levels.

What is the significance of the ventilatory threshold?

It indicates a disproportionate increase in VCO2 and VE relative to workload.

What is VO2 max?

The maximum amount of energy that can be transported and utilized within the working muscle.

What factors affect VO2 max?

Genetic make up, level of conditioning, age, and gender.

What is the role of the immune system?

Monitoring tissue homeostasis, protecting against foreign substances, and eliminating damaged self.

What are the primary components of the immune system?

Molecules/proteins, cells, and tissues.

What distinguishes innate immunity from adaptive immunity?

Innate immunity works rapidly and is non-specific; adaptive is slower and more specific with memory cells.

What is the purpose of clonal proliferation in T cells?

It is the rapid multiplication of a specific type of T cell after it recognizes an antigen.

How does exercise affect the immune system?

Moderate exercise improves immune function, while heavy exercise can increase the risk of infections.

What is the importance of the Valsalva maneuver?

It increases intrathoracic pressure, affecting blood return and oxygenation.

What happens to pulmonary function with age?

Residual lung volume increases with age, but is blunted in older athletes due to exercise.

What triggers the urge to breathe?

An increase in the arterial partial pressure of carbon dioxide (PCO2).

What is hyperventilation's effect on oxygen levels?

It can lead to a drop in arterial carbon dioxide, extending breath-holding capacity.

What is the Bohr effect?

Lower pH increases the release of oxygen from hemoglobin.

What are the components of blood?

Formed elements (RBCs, WBCs, platelets) and plasma.

How is oxygen transported by hemoglobin?

Around 98% of oxygen is transported bound to hemoglobin.

What is the role of erythropoietin (EPO)?

EPO stimulates red blood cell production in response to low oxygen levels.

What factors influence hemoglobin's oxygen-carrying capacity?

Amount of hemoglobin, partial pressure of oxygen, and pH.

What adaptations occur in athletes living at high altitude?

Increase in red blood cells and hemoglobin concentration.

What is the arteriovenous oxygen difference (AVO2)?

The difference in oxygen content between arterial and venous blood.

What increases during high-intensity exercise?

The arteriovenous oxygen difference (AVO2) increases.

What is the role of carbonic anhydrase?

It catalyzes the formation of carbonic acid from carbon dioxide and water.

What mechanisms facilitate oxygen release from hemoglobin during exercise?

Higher temperature, increased CO2, and lowered pH (Bohr effect).

How does the respiratory system respond to increased blood acidity?

Increased ventilation frequency and depth to normalize pH.

What is the primary function of the chemoreceptors?

To monitor changes in blood gases and pH, adjusting ventilation accordingly.

How do proprioceptors influence ventilation?

They increase ventilation during movement by sending signals to the respiratory centers.

What happens to blood oxygen levels during intense exercise?

Partial pressure of oxygen in the blood decreases as oxygen is used by muscles.

What is the significance of the oxyhemoglobin dissociation curve?

It illustrates how hemoglobin saturation varies with partial pressure of oxygen.

How does exercise influence the oxyhemoglobin dissociation curve?

During exercise, the curve shifts to the right, promoting oxygen release.

What is the primary factor that drives gas exchange in the lungs?

The partial pressure differences of oxygen and carbon dioxide.

How does blood flow in the pulmonary circuit change during exercise?

Pulmonary volume can increase nearly threefold with minimal increase in pulmonary pressure.

What adaptations occur in the lungs due to chronic exercise?

Increased compliance and efficiency of the respiratory muscles.

What is the role of the medulla in ventilation control?

Coordinates inspiratory and expiratory centers to regulate breathing.

What can impede gas exchange during pulmonary issues?

Increased thickness of the alveolar-capillary membrane.

What is a typical tidal volume at rest?

Approximately 0.5 liters (500 ml).

What changes occur to tidal volume during exercise?

Tidal volume increases, primarily utilizing inspiratory reserve volume.

How does the body ensure adequate oxygen delivery during exercise?

By increasing cardiac output and extracting more oxygen from the blood.

What defines the concept of 'oxygen debt'?

The increased demand for oxygen after switching from aerobic to anaerobic metabolism.

What is the maximum ventilation achieved by elite athletes during intense exercise?

Can increase to approximately 150 liters per minute.

How do decreased oxygen levels and high CO2 levels affect breathing?

They stimulate increased respiratory rate and depth.

What happens to the concentrations of oxygen and carbon dioxide in muscle during high-intensity exercise?

Oxygen levels drop and carbon dioxide levels increase.

How do conditions such as pulmonary edema affect exercise performance?

They impede gas exchange and decrease performance.

What role does cortisol play during physical stress on the body?

It regulates processes such as glucose metabolism and immune function.

What is the importance of adequate hydration during exercise?

It helps maintain blood volume and ensures efficient thermoregulation.

What defines minute ventilation?

The volume of air that passes through the lungs each minute.

What is the relationship between body temperature and oxygen delivery?

Higher body temperatures can enhance the release of oxygen from hemoglobin.

How does the respiratory system contribute to acid-base balance during exercise?

By adjusting the rate of CO2 expulsion and managing blood pH.

What adaptations in muscles improve oxygen extraction and use during exercise?

An increase in capillarity and the number of mitochondria.

How does physical training impact respiration?

It increases the efficiency and endurance of respiratory muscles.

What is the primary energy source during rest?

Fat, accounting for 60% of energy supply.

How does lactic acid impact performance during exercise?

It contributes to fatigue and can signal the need for a reduction in intensity.

What physiological changes occur with aging in relation to lung function?

Residual volume increases while lung capacity may remain unchanged.

How is maximal oxygen uptake clinically significant?

It reflects an individual's aerobic capacity and overall fitness level.

What is a common effect of long-term untrained states on the respiratory system?

Reduced ventilation efficiency and lower exercise tolerance.

Why do lean individuals typically have higher fat reserves?

Because lean individuals can store more energy as fat.

What is the significance of pulmonary capillary recruitment during exercise?

It enhances gas exchange by increasing the surface area for diffusion.

How does blood flow to the lungs adapt during intense exercise?

The lungs recruit closed capillaries to support increased blood volume.

What can cause a decrease in arterial blood pH during exercise?

Increased lactate from anaerobic metabolism.

What is the relationship between trained status and respiratory efficiency?

Trained individuals have improved lung function and oxygen uptake.

What does the term 'exercise-induced arterial hypoxemia' refer to?

A reduction in blood oxygen levels during intense physical activity.

Why is adequate ventilation critical during prolonged exercise?

To ensure sufficient oxygen delivery and CO2 removal.

What cellular adaptations occur with lung training?

Increased number of alveoli and improved surface area for gas exchange.

What is a key consideration for athletes training at high altitude?

Acclimatization is essential for optimal performance due to lower oxygen availability.

Why might elite athletes demonstrate higher ventilation rates?

Due to larger lung volumes and efficient gas exchange capabilities.

What oxygen-related safety concerns exist for divers?

Nitrogen narcosis and decompression sickness are risks at depth.

During exercise, how do muscles influence pulmonary ventilation?

Muscles provide feedback to increase ventilation rates proportionate to demands.

What effect does the Valsalva maneuver have on blood flow?

It can decrease venous return and lower blood pressure temporarily.

What is the long-term adaptation of blood volumes in highly trained athletes?

Increased plasma volume enhances endurance capacity.

What factors influence the solubility of gases in blood?

Gas molecular weight and partial pressure.

How does ion exchange facilitate gas transport?

Chloride shifts assist in maintaining bicarbonate levels during gas exchange.

What physiological response is triggered by elevated carbon dioxide levels?

Increased depth and frequency of breathing.

How is oxygen delivery maximized during high-intensity exercise?

Increased blood flow to active tissues enhances delivery.

What adaptations improve aerobic metabolism during exercise training?

Increased mitochondrial density and capillary networks.

What can result from an imbalance in ventilation and perfusion during vigorous exercise?

Reduced efficiency in oxygen uptake and CO2 removal.

What role do central and peripheral chemoreceptors play in respiration?

They monitor blood gas levels and adjust ventilation in response.

What describes the function of stretch receptors in the lungs?

They help regulate the depth and rate of breathing based on lung inflation.

What correlates with the increase in VCO2 during exercise?

An increase in metabolic activity and lactic acid production.

What is the relationship between exercise intensity and blood lactate accumulation?

As intensity increases, blood lactate levels rise significantly.