Exercise Physiology: Respiratory Function

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What primarily stimulates pulmonary ventilation during muscle exercise?

  • Decreased oxygen levels in the blood
  • Chemical changes in the heart
  • Increased barometric pressure
  • Neurogenic impulses to the respiratory centers (correct)

What is the primary purpose of increasing pulmonary ventilation during muscle exercise?

  • To enhance digestion
  • To stabilize blood pressure
  • To supply extra O2 and remove CO2 (correct)
  • To cool the body down

Which component does NOT directly influence the regulation of ventilation during exercise?

  • Respiratory centers in the brain stem
  • Change in the carbon dioxide levels
  • Neurogenic impulses
  • Oxygen transport in the bloodstream (correct)

What happens to the arterial PO2 and PCO2 values during light to moderate exercise?

<p>They remain unchanged. (C)</p> Signup and view all the answers

During muscle exercise, what happens to the levels of CO2 in the body?

<p>They increase and are subsequently removed (B)</p> Signup and view all the answers

Which physiological mechanism is most critical for increasing pulmonary ventilation during physical activity?

<p>Neurogenic signals to the respiratory centers (A)</p> Signup and view all the answers

In which scenario is lactic acid accumulation likely to occur?

<p>During severe and sustained exercise. (D)</p> Signup and view all the answers

What effect does severe exercise have on blood pH?

<p>It drops to approximately 7.2. (A)</p> Signup and view all the answers

How does pulmonary ventilation respond to metabolic demands during exercise?

<p>It is well matched. (C)</p> Signup and view all the answers

Which of the following is NOT true regarding blood gases during exercise?

<p>PCO2 significantly increases during light exercise. (C)</p> Signup and view all the answers

What is the saturation level of hemoglobin (Hb) with oxygen (O2) in tissues during exercise at a PO2 of 20 mmHg?

<p>20% (B)</p> Signup and view all the answers

How much oxygen do tissues extract from arterial blood during exercise at 20 mmHg PO2?

<p>About 50% (D)</p> Signup and view all the answers

What percentage of transported O2 primarily supplies the oxygen needs of tissues?

<p>98% (B)</p> Signup and view all the answers

What effect does exercise have on the oxyhemoglobin dissociation curve?

<p>It shifts to the right. (A)</p> Signup and view all the answers

What percentage of oxygen is hemoglobin estimated to hold in tissues at 20 mmHg PO2 during exercise?

<p>20% (B)</p> Signup and view all the answers

Oxygen content is defined as what?

<p>The volume of O2 carried by blood combined with hemoglobin per 100 ml of blood (B)</p> Signup and view all the answers

Which of the following factors can contribute to a rightward shift in the oxyhemoglobin dissociation curve during exercise?

<p>Increased temperature (D)</p> Signup and view all the answers

Which factor does NOT influence hemoglobin saturation with oxygen?

<p>Blood volume (B)</p> Signup and view all the answers

What is the appropriate measurement unit for oxygen content?

<p>Milliliters per 100 ml of blood (B)</p> Signup and view all the answers

What is the relationship between hemoglobin and oxygen transport?

<p>Hemoglobin significantly increases the capacity of blood to transport oxygen (A)</p> Signup and view all the answers

What does the term 'diffusion' refer to in the context of oxygen transport?

<p>The movement of oxygen from high to low pressure areas in the lungs (A)</p> Signup and view all the answers

How is oxygen primarily transported in the blood?

<p>By being physically dissolved in the plasma and bound to hemoglobin (C)</p> Signup and view all the answers

What influences the rate of oxygen diffusion into the blood?

<p>The difference in partial pressure of oxygen (B)</p> Signup and view all the answers

Which statement accurately describes a factor that affects oxygen transport in the blood?

<p>Higher temperatures decrease the solubility of oxygen in plasma (A)</p> Signup and view all the answers

What is the significance of the difference in alveolar and pulmonary blood oxygen pressure?

<p>It influences the diffusion rate of oxygen into the bloodstream (B)</p> Signup and view all the answers

What physiological change is associated with an increase in carbon dioxide (PCO2)?

<p>Decrease in pH and increase in H+ concentration (A)</p> Signup and view all the answers

Which factor is NOT a consequence of increased temperature in metabolic processes?

<p>Decreased production of 2,3-DPG (C)</p> Signup and view all the answers

What role does 2,3-diphosphoglycerate (2,3-DPG) play in red blood cells?

<p>It decreases hemoglobin's affinity for oxygen. (B)</p> Signup and view all the answers

How does an increase in H+ concentration affect pH levels?

<p>It decreases pH, making the solution more acidic. (C)</p> Signup and view all the answers

Which statement accurately describes the effect of elevated levels of carbon dioxide in the bloodstream?

<p>It causes a decrease in blood pH. (C)</p> Signup and view all the answers

Flashcards

Pulmonary ventilation

The process of moving air in and out of the lungs.

Arterial PO2

The pressure of oxygen in the arterial blood.

Arterial PCO2

The pressure of carbon dioxide in the arterial blood.

Blood pH

A measure of acidity in the blood.

Signup and view all the flashcards

Lactic acid accumulation

A build-up of lactic acid in the blood, often during strenuous exercise.

Signup and view all the flashcards

Perfusion

The flow of blood through the lungs.

Signup and view all the flashcards

Oxygen Supply During Exercise

The amount of oxygen supplied to the body during exercise increases to meet the demands of the muscles.

Signup and view all the flashcards

Carbon Dioxide Removal During Exercise

The amount of carbon dioxide removed from the body during exercise increases to balance the increased production of carbon dioxide by the muscles.

Signup and view all the flashcards

Neurogenic Impulses and Ventilation Control

Nerves send signals to the brain stem, which controls breathing, to increase ventilation during exercise.

Signup and view all the flashcards

Hemoglobin

The main source of oxygen for the body's tissues.

Signup and view all the flashcards

Oxygen Diffusion Capacity

The amount of oxygen that diffuses across the lung membrane per minute, for each millimeter of mercury difference in pressure between the alveoli and the blood.

Signup and view all the flashcards

Oxygen Transport in Blood

Oxygen is carried in the blood in two ways: dissolved in the plasma and bound to hemoglobin.

Signup and view all the flashcards

Oxygen content

The amount of oxygen carried by 100 ml of blood.

Signup and view all the flashcards

Oxygen capacity

The maximum amount of oxygen that can be carried by 100 ml of blood.

Signup and view all the flashcards

Dissolved Oxygen

Oxygen that is physically dissolved in the blood plasma.

Signup and view all the flashcards

Hemoglobin

The protein in red blood cells that binds to oxygen, allowing for efficient transport.

Signup and view all the flashcards

Hemoglobin saturation

The percentage of hemoglobin that is bound to oxygen.

Signup and view all the flashcards

Alveolar Partial Pressure of Oxygen (PAO2)

The partial pressure of oxygen in the alveoli (tiny air sacs in the lungs).

Signup and view all the flashcards

Hemoglobin's role in oxygen transport

It transports approximately 98% of the oxygen in the blood.

Signup and view all the flashcards

Hemoglobin Saturation During Exercise

During exercise, the oxygen saturation of hemoglobin in tissues is around 20% when the partial pressure of oxygen (PO2) is 20 mmHg.

Signup and view all the flashcards

Tissue Oxygen Uptake

Tissues utilize approximately 50% of the oxygen delivered by arterial blood when the PO2 is 20 mmHg.

Signup and view all the flashcards

Right Shift of Oxyhemoglobin Dissociation Curve

A shift in the oxyhemoglobin dissociation curve to the right indicates that hemoglobin releases oxygen more readily at a given PO2.

Signup and view all the flashcards

Factors Affecting Oxygen Release

Increased temperature, elevated carbon dioxide levels, and decreased pH (acidity) all facilitate the release of oxygen from hemoglobin.

Signup and view all the flashcards

Physiological Importance of Right Shift

The rightward shift of the oxyhemoglobin dissociation curve during exercise ensures that tissues receive adequate oxygen despite increased demand.

Signup and view all the flashcards

Increased PCO2

An increase in the partial pressure of carbon dioxide (CO2) in the blood.

Signup and view all the flashcards

Increased Temperature

A rise in the temperature of the blood.

Signup and view all the flashcards

Decreased pH and Increased H+

A decrease in blood pH, making it more acidic, and an increase in the concentration of hydrogen ions (H+).

Signup and view all the flashcards

Increased 2,3-DPG

An increase in the concentration of 2,3-diphosphoglycerate (2,3-DPG) in red blood cells (RBCs).

Signup and view all the flashcards

2,3-Diphosphoglycerate (2,3-DPG)

This is a by-product of red blood cell metabolism. It affects the affinity of hemoglobin for oxygen, making it harder for the hemoglobin to hold onto oxygen.

Signup and view all the flashcards

Study Notes

Respiratory Regulation during Exercise

  • Cells during exercise increase O2 consumption and CO2 production by 20-fold.
  • Pulmonary ventilation and perfusion increase to meet the demand for O2 and remove excess CO2.
  • Pulmonary ventilation is controlled by neurogenic impulses to the respiratory centers in the brainstem.

Blood Gases and Exercise

  • Pulmonary ventilation is well adjusted to metabolic demands during light to moderate exercise.
  • Arterial PO2, PCO2, and H+ values remain unchanged during light to moderate exercise.
  • Severe sustained exercise can cause lactic acid buildup, and a drop in pH (to 7.2), resulting in hyperventilation.

Muscle, Tendons, and Joint Receptors

  • Impulses from proprioceptors in muscles, tendons, and joints stimulate respiratory centers during movement.

Higher Brain Centers

  • As exercise begins, brain impulses to muscles and collateral impulses stimulate respiratory centers (RC).
  • Experienced athletes experience increased respiration before the actual start of exercise (conditioned reflexes).

Increased Tissue Metabolism and Temperature

  • Increased tissue metabolism and temperature stimulate respiratory centers (via impulses to the hypothalamus).

Increased Venous Return

  • Increased venous return stimulates cardiac mechanoreceptors in the right atrium, which stimulate respiration.

Norepinephrine

  • Norepinephrine released from the sympathetic nervous system stimulates respiratory centers (RC).

Oxygen Supply to Muscles

  • Oxygen supply to muscles is also increased through gas diffusion, shifting the O2 dissociation curve (to the right) and increasing cardiac output.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Lec 6 Respiratory Regulation 2024 PDF

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser