STUDY QUESTIONS STRUCTURE AND FUNCTION OF RESPIRATORY SYSTEM

Question 1

1. How does the larynx function in breathing and voice production?

Answer 1

True Vocal Cord- speech
False Vocal Cord - hold breath

Question 2

2. Where are the lungs located? Distinguish the parietal pleura from the visceral pleura.

Answer 2

Thoracis Cavity

The parietal pleura is the outer layer of the pleural membrane, which lines the inner surface of the rib cage, the diaphragm, and the mediastinum

The visceral pleura is the inner layer of the pleural membrane, which covers the outer surface of the lungs. The visceral pleura is in direct contact with the lungs and is more intimately attached to the lung tissue than the parietal pleura.

Question 3

3. Where in the lungs does the exchange of O2 and CO2 take place?

Answer 3

The exchange of oxygen (O2) and carbon dioxide (CO2) takes place in the lungs at the level of the alveoli.

Respitory zone

Question 4

4. Compare what happens during quite breathing versus labored breathing.

Answer 4

Eupnea, is normal, relaxed, and effortless breathing that occurs at a rate of 12-20 breaths per minute.

Passive

Active

Question 5

5. What is the basic difference between a lung volume and a lung capacity?

Answer 5

Lung volume refers to the amount of air that is present in the lungs at a particular moment in time. example Tidal volumn

Lung capacity, on the other hand, refers to the maximum amount of air that the lungs can hold. example total lung capacity

Question 6

6. What is tidal volume?

Answer 6

Tidal volume is the volume of air inhaled and exhaled with each normal breath.

500 mL

Question 7

7. Compare and contrast vital capacity versus total lung capacity

Answer 7

Vital capacity (VC) is the maximum amount of air that can be exhaled after taking a deep breath.

Total lung capacity (TLC), on the other hand, is the sum of all the lung volumes, including tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume.

Question 8

8. In a person at rest, what is the partial pressure difference that drives diffusion of oxygen into the blood in pulmonary ventilation?

Answer 8

When a person inhales air, the oxygen in the air enters the alveoli, increasing the PAO2. At the same time, the oxygen diffuses into the arterial blood, increasing the partial pressure of oxygen in arterial blood (PaO2).

The greater the difference in partial pressure, the faster the diffusion of oxygen occurs.

760 of all atmosphere
158 air
105 in the avioli
Lvl of Co2 in the tissue compared to the capilaries 45 in the tissue and 40 in the cap
75% is inhaled
70% of oxygen is used.
30% is dead space

Question 9

9. What is the relationship between hemoglobin and PO2?

Answer 9

The amount of oxygen that hemoglobin can bind to is dependent on the partial pressure of oxygen (PO2) in the surrounding environment. At a high PO2, such as in the lungs, hemoglobin readily binds to oxygen, forming oxyhemoglobin. As the oxygen-rich blood travels through the circulatory system and reaches the tissues, the PO2 decreases, causing the hemoglobin to release its oxygen.

Question 10

10. What factors cause hemoglobin to unload more oxygen as blood flows through the capillaries of metabolically active tissues, such as skeletal muscle during exercise?

Answer 10

Carbon Dioxide
Acidity
Temperature

Question 11

1. a. Describe the respiratory system role with oxygen and carbon dioxide.

b. Why is oxygen needed?

c. What generates CO2?

Answer 11

• a. O2 to the body’s cells and to remove CO2, which is produced as a byproduct of cellular respiration.
• b. A process that generates energy for the body uses O2.
• c. When cells break down glucose to release energy, they produce CO2 as a waste product.

Question 12

2. Define the three important continuous physiological processes that are responsible
   for the movement of oxygen and carbon dioxide.
   a. Ventilation

b. Gas Exchange

c. Gas Transport

Answer 12

Ventilation refers to the movement of air in and out of the lungs

Gas exchange refers to the transfer of oxygen from the alveoli (air sacs in the lungs) into the bloodstream and the removal of carbon dioxide from the bloodstream into the alveoli.

Gas transport refers to the movement of oxygen and carbon dioxide in the bloodstream, through the circulatory system, to and from the body’s tissues.

Question 13

3. Explain the correlation between gas pressure and concentration.

Answer 13

Gas pressure and concentration are directly proportional, meaning that as the pressure of a gas increases, so does its concentration.

Question 14

4. Define partial pressure.

Answer 14

Partial pressure is the pressure exerted by a particular gas in a mixture of gases. partial pressure is used to describe the pressure exerted by oxygen (PO2) and carbon dioxide (PCO2) in the blood and alveolar air.

Question 15

5. Describe how partial pressure determines movement of specific gas molecules in a mixture.

Answer 15

According to the gas laws, gases will tend to move from an area of high partial pressure to an area of low partial pressure.

Question 16

6. Why would oxygen diffuse into this blood vessel while carbon dioxide diffuses out? Contrast External and Internal respiration.

Answer 16

The oxygen diffuses into the blood vessel because it is driven by a partial pressure gradient. The partial pressure of oxygen in the blood is lower than in the alveoli, so the oxygen will move from an area of high partial pressure to an area of low partial pressure.

Question 17

7. Define external respiration.

Answer 17

External respiration refers to the exchange of oxygen and carbon dioxide between the air in the lungs and the blood in the pulmonary capillaries.

Question 18

8. What is the critical function of ventilation?

Answer 18

Ventilation is a critical function of the respiratory system that refers to the movement of air into and out of the lungs. Ventilation helps to remove waste carbon dioxide from the body and bring in oxygen to the blood, which is necessary for the body’s cells to function properly.

Question 19

9. Contrast the P02 (oxygen partial pressure) in the lungs (alveoli) and in the surrounding blood capillaries.

a. Contrast the PCO2 (carbon dioxide partial pressure) in the lungs (alveoli) and in the
surrounding blood capillaries.

b. Gas diffusion is dependent upon the partial pressure of gasses. Explain the
movement of the following gasses between lung alveoli and blood capillaries as a
function of their relative partial pressures in each location.

Oxygen -
Carbon Dioxide –

Answer 19

The P02 in the lungs (alveoli) is higher than the P02 in the surrounding blood capillaries.

The PCO2 in the lungs (alveoli) is lower than the PCO2 in the surrounding blood capillaries.

Oxygen diffuses from the alveoli, where the partial pressure of oxygen is higher, into the blood capillaries, where the partial pressure of oxygen is lower.

Carbon dioxide diffuses from the blood capillaries, where the partial pressure of carbon dioxide is higher, into the alveoli, where the partial pressure of carbon dioxide is lower.

Question 20

10. Define internal respiration.

Answer 20

Internal respiration refers to the exchange of oxygen and carbon dioxide between the blood in the systemic capillaries and the cells of the body. In both cases, the exchange occurs because of a gradient of partial pressure, with oxygen diffusing into the blood and carbon dioxide diffusing out.

Question 21

11. Contrast the P02 (oxygen partial pressure) in the blood capillaries and in the cells of the
    surrounding tissues.

a. Contrast the PCO2 (carbon dioxide partial pressure) in the blood capillaries and in
the cells of the surrounding tissues.

b. Explain the movement of the following gasses between blood capillaries and
tissue cells as a function of their relative partial pressures in each location.

Oxygen –
Carbon Dioxide -

Question 22

1. a. Describe normal ventilation as a continuous cycle of inspiration and expiration.

b. What regulates this continuous cycle?

Answer 22

inspiration, also known as inhalation, involves the contraction of the diaphragm and the external intercostal muscles, causing the chest cavity to expand and increase pressure within the lungs. This pressure difference creates a gradient for air to flow into the lungs.

Phenic nerve and intercostal nerve DRG

expiration, or exhalation, the diaphragm and external intercostal muscles relax, causing the chest cavity to decrease in size and the pressure within the lungs to return to atmospheric pressure, forcing air out of the lungs.

Need for oxygen, the level of carbon dioxide in the blood, and the level of hydrogen ions

Question 23

2. Explain the role of the inspiratory and expiratory areas of the brain.

Answer 23

inspiratory area Medulla oblongata, signals the diaphragm and intercostal muscles to contract and increase the volume of the thorax, causing air to flow into the lungs.

expiratory area, also located in the medulla oblongata, signals the diaphragm and intercostal muscles to relax and decrease the volume of the thorax, causing air to flow out of the lungs.

Question 24

3. What is a spirogram?

Answer 24

A spirogram is a graphical representation of the volume and flow of air during respiration and compacity.

Used to evaluate the health of the respiratory system and to diagnose a variety of conditions, such as asthma, chronic obstructive pulmonary disease (COPD), and restrictive lung diseases.

Question 25

4. a. Describe inspiration stimulation by the inspiratory area of the brain.

b. Describe passive expiration.

Answer 25

The inspiratory area of the brain is responsible for initiating the process of inspiration or inhalation.

Passive expiration is the process of air leaving the lungs without conscious effort. It occurs when the muscles responsible for inspiration relax, and the thorax returns to its original size.

Question 26

5. Explain the role of accessory inspiratory muscles and how they are stimulated during forced inspiration.

Answer 26

Accessory inspiratory muscles include the intercostal muscles, the scalene muscles, and the sternocleidomastoid muscles.

An increased demand for oxygen, such as during exercise or heavy physical activity.

Question 27

6. Explain stimulation and the role of the expiratory area during forced expiration.

Answer 27

This process is important for clearing the lungs of excess air, for expelling mucus, and for speech production.

Question 28

7. Describe the role of the pontine respiratory group in relation to the:
   Dorsal respiratory group

Ventral respiratory group

Answer 28

The pontine respiratory group is a part of the central respiratory control system in the brainstem that plays a role in regulating breathing. It is responsible for coordinating and integrating the activities of the dorsal and ventral respiratory groups.

The dorsal respiratory group is located in the medulla oblongata and primarily controls the rhythm and pattern of breathing, including breathing rate and tidal volume.

The ventral respiratory group is located in the medulla oblongata and pons, and it mainly controls the amplitude and intensity of breathing, including activation of accessory muscles during exertion or heavy breathing.

Question 29

8. Describe how the hypothalamus contributes to ventilation regulation.

Answer 29

The hypothalamus receives information about the body’s carbon dioxide levels and oxygen levels, as well as signals from stretch receptors in the lungs and blood vessels. It then sends signals to the respiratory control centers in the brainstem to adjust breathing rate and depth as needed to maintain normal levels of oxygen and carbon dioxide in the body.

Question 30

9. a. Describe how the cerebral cortex supplies a limited level of respiratory control.

b. Why is cortical control essential?

Answer 30

• a. Modulate and fine-tune the automatic and unconscious control mechanisms of the respiratory system.
• b. breathing during sleep
• such as during exercise

Question 31

10. What is function of chemoreceptors in the central and peripheral nervous systems.

Answer 31

Central Chemoreceptors for CO2

Peripheral Chemoreceptors for O2

• Maintaining homeostasis
• medulla oblongata
• carotid and aortic bodies

Question 32

11. a. Describe the respiratory response to increasing CO2 and H+ as detected by chemoreceptors.

b. Define hyperventilation

c. How do these adjustments contribute to homeostasis?

Answer 32

• When the levels of CO2 and H+ increase in the blood, the chemoreceptors detect this change and trigger a respiratory response. This response is characterized by an increase in the rate and depth of breathing, which helps to remove excess CO2 from the body. This process is known as hyperventilation.
• Hyperventilation is defined as an excessive increase in the rate and depth of breathing, leading to a decrease in the levels of CO2 in the blood.
• Keeping the levels of CO2 and H+ within a narrow range that is necessary for proper physiological function. By controlling the levels of CO2 and H+, the chemoreceptors help to ensure that the body’s acid-base balance is maintained and that the body is able to function effectively.

Question 33

12. a. Describe the respiratory response to decreasing CO2 and H+ as detected by chemoreceptors.

b. Define hypoventilation.

c. How do these adjustments contribute to homeostasis?

Answer 33

• a. The respiratory response to decreasing CO2 and H+ as detected by chemoreceptors is decreased ventilation, leading to an increase in CO2 and H+ levels in the blood. This is known as hypoventilation.
• b. Hypoventilation refers to a decrease in the rate and depth of breathing, resulting in a buildup of CO2 and H+ in the blood.
• c. These adjustments help to maintain the balance or homeostasis of the body’s pH levels. The chemoreceptors detect changes in CO2 and H+ levels and respond by adjusting the rate and depth of breathing to maintain the proper balance. When CO2 levels rise and H+ levels decrease, breathing increases, and when CO2 levels decrease and H+ levels increase, breathing decreases, helping to maintain the proper balance of these important bodily substances.