Exam Respiratory System 4 Physiology

19. The volume of air exchanged with the environment during an unforced breath is called

- Tidal volume

As the volume of the lung increases, atmospheric pressure

- Will not change (atmospheric pressure is an ocean compared to the lungs the volume of lungs will not affect the atmospheric pressure) - However, as the volume of the lung increases pressure within the lung decreases causing the lungs to have less pressure than the atmospheric pressure (inhalation). Atmospheric pressure always remains constant at 760mmHG. - Inspiration occurs when pressure in the alveoli is less than atmospheric pressure - Exhalation occurs when pressure in the alveoli is greater than atmospheric pressure.

49. What percentage of air is carbon dioxide?

.03% = .0003 less than 1 percent

36. When air is no longer moving through the respiratory tract and the airway is open to the environment, the pressure within the lung is equal to

0mmHg= atmospheric pressure

51. What percentage of the oxygen transported in whole blood is transported in the plasma?

1.5% Every liter of arterial blood contains about 200mL of oxygen. Approximately 3mL of this oxygen (1.5%) is dissolved in the plasma or in the cytosol of the erythrocytes, and only this dissolved oxygen contributes to the PO2 in the blood. The remaining 98.5% is transported bound to hemoglobin. Although the bound oxygen does not contribute to the PO2, it is in equilibrium with the dissolved oxygen, and thus the amount of oxygen bound to hemoglobin is a function of PO2.

7. Assuming resting conditions at sea level, what is the partial pressure of oxygen in alveoli?

100 mm Hg

9. Assuming resting conditions at sea level, what is the partial pressure of oxygen in pulmonary veins?

100 mmHg

11. Assuming resting conditions at sea level, what is the partial pressure of oxygen in systemic arteries?

100mmHg

28. In the systemic arteries, the partial pressure of oxygen is approximately ________, and hemoglobin is approximately ________ saturated with oxygen.

100mmHg; 98%

16. At an altitude where atmospheric pressure is 500 mm Hg, what is the partial pressure of oxygen?

105 mm Hg because Oxygen is 21% so 500 x .21= 105mm Hg

6. Assuming resting conditions at sea level, what is the partial pressure of oxygen in air?

160mm Hg , P02 is 21% of atmospheric pressure

46. What is the partial pressure of oxygen in air at sea level?

160mmHg 21%

44. What is the partial pressure of nitrogen if it accounts for 20% of a mixed gas with a total pressure of 1000 mm Hg?

200mmHg

50. What percentage of air is oxygen?

21%

18. At sea level, if oxygen is consumed by the body cells at a rate of 300 mL per minute, then how much oxygen diffuses from the alveoli into the blood in the pulmonary capillaries?

300 mL per minute

13. Assuming resting conditions at sea level, what is the partial pressure of oxygen in systemic veins?

40 mm Hg

15. Assuming resting conditions at sea level, what is the partial pressure of oxygen in pulmonary arteries?

40 mm Hg

27. In the pulmonary arteries, the partial pressure of oxygen is approximately _____40 mmHg___, and hemoglobin is approximately ___75%_____ saturated with oxygen.

40 mmHg; 75%

45. What is the partial pressure of oxygen in a gas mixture that is 40% oxygen, 40% argon, and 20% helium, when the total pressure of the gas is 1000 mm Hg?

400mm Hg

12. Assuming resting conditions at sea level, what is the partial pressure of carbon dioxide in systemic arteries?

40mm Hg

10. Assuming resting conditions at sea level, what is the partial pressure of carbon dioxide in pulmonary veins?

40mmHg

8. Assuming resting conditions at sea level, what is the partial pressure of carbon dioxide in alveoli?

40mmHg

A normal vital capacity is approximately

4500mL

14. Assuming resting conditions at sea level, what is the partial pressure of carbon dioxide in systemic veins?

46 mm Hg

A normal tidal volume at rest is approximately

500 mL - Tidal volume is the volume of air that moves into and out of the lungs during a single unforced breath

43. What is the normal pH range for blood?

7.38- 7.42

17. At sea level the air pressure which equals 1 atmosphere is

760 mm Hg

4. As it leaves the lung in the pulmonary vein, blood is ________ saturated with oxygen.

98%

41. What is the definition of anemia?

A decrease in the oxygen carrying capacity of the blood

8. Equilibration of pressure between the intrapleural space and the alveoli will lead to which of the following?

A pneumothorax (the lung will collapse). Pressure is always negative in the intrapleural space so that the alveoli can have more pressure to keep the alveoli from collapsing Intra pleural pressure needs to be less to keep alveolar expanded. If puncture to intrapleural space this would cause more pressure in intrapleural space and decrease pressure in alveoli which would cause the lung to collapse.

37. Which cells engulf foreign particles that reach the lungs?

Alveolar macrophages

17. The surface tension of the alveolus is reduced by surfactants produced by what type of cells?

Alveolar type II cells - produce pulmonary surfactant

48. What is the primary mechanism of carbon dioxide transport in blood?

As bicarbonate dissolved in plasma

11. The difference between what two pressures drives air into and out of the lungs?

Atmospheric and intra-alveolar pressure When atmospheric pressure exceeds intra-alveolar pressure (when intra-alveolar pressure is negative), inspiration occurs When intra-alveolar pressure exceeds atmospheric pressure (when intra-alveolar pressure is positive), expiration occurs

48. Which pressure is constant during the respiratory cycle?

Atmospheric pressure

43. Which of the following pressures is lower during inspiration than during expiration?

Both intra-alveolar and intrapleural pressures

35. The majority of oxygen present within the blood is

Bound to hemoglobin in red blood cells

1. A change in the ratio of bicarbonate to carbon dioxide concentration in the blood will

Change blood pH

22. During quiet breathing, a person's breathing cycle consists of

Contraction and relaxation of inspiratory muscles

39. What is labored or difficult breathing called?

Dyspnea

30. What is the significance of the respiratory membrane to facilitate gas exchange?

Epithelial and endothelial cells share a common basement membrane

24. What are the most common cells that line the surface of the alveoli and are therefore associated with the exchange of gases within the lungs?

Epithelium -Alveolar Type I Cells

27. What is the function of alveolar pores?

Equalizes pressure in lungs

42. Which of the following occurs when intra-alveolar pressure exceeds atmospheric pressure?

Expiration - air moves out of the lungs

14. The maximum volume of air that can be expired following a resting expiration is called

Expiratory reserve volume (ERV) - average 1000mL

25. What are the primary inspiratory muscles?

External intercostal muscles Diaphragm

29. What is the residual volume + expiratory reserve volume called?

Functional Residual Capacity

35. What is the volume of air present in the lungs when the lungs are at rest (in between breaths)?

Functional Residual Capacity Not Residual Capacity because that is when you exhale normally (Tidal wave) you still are left with the IRV (Inspiratory Reserve Volume) and Residual Capacity. Only Residual Capacity when you use IRV (Inspiratory Reserve Volume)

20. The volume of air in the lungs at rest, between breaths, is called

Functional residual capacity (average 1200mL) Intra-alveolar pressure= atmospheric pressure = 0mmHg NOT residual volume because residual volume is the amount of air in the lungs after maximum expiration.

33. The buffering capacity of hemoglobin is directly related to its ability to bind with

Hydrogen ions

38. What is an increase in alveolar ventilation to match the demands of increased metabolic activity in the cells called?

Hypernea

30. Oxygen-rich blood is found in which of the following?

Hypoventilation

31. Respiratory acidosis can occur during

Hypoventilation

37. What is a deficiency of oxygen in the tissues called?

Hypoxia

34. The carbamino effect describes a change in the conformation of hemoglobin that is induced by a(n)

Increase in CO2

2. As a result of hyperventilation, a patient would eventually experience a(n) ________ within the systemic arteries.

Increase in PO2 and decrease in PCO2

32. Respiratory acidosis will result from a(n)

Increase in blood CO2 concentration

As the volume of the chest wall increases, the concomitant (naturally occurring) expansion of the lungs is due to a(n)

Increase in transpulmonary pressure - Transpulmonary pressure- the difference between the intrapleural pressure and the intra-alveolar pressure. - An increase in transpulmonary pressure creates a larger distending pressure across the lungs, which is accompanies by the expansion(increased volume) lungs (alveoli).

26. What does contraction of the diaphragm cause?

Increased volume in thoracic cavity and therefore a decrease in intra-alveolar pressure

23. Tidal volume + inspiratory reserve volume is called

Inspiratory capacity (IC) - the maximum volume of air that can be inspired at the end of a resting expiration (averages 3500)

18. The tidal volume and inspiratory reserve volume together make up which of the following?

Inspiratory capacity (IC)- the maximum volume of air that can be inspired at the end of a resting expiration (averages 3500 mL)

40. Which of the following has the difference between its pressure and atmospheric pressure driving the air into and out of the lungs?

Intra- alveolar pressure

46. Which pressure changes with the phases of respiration from a negative value during inspiration and a positive value during expiration?

Intra- alveolar pressure

45. Which pressure changes with the phases of respiration but is always negative?

Intrapleural pressure

47. Which pressure equals atmospheric pressure during a pneumothorax, causing the lungs to collapse?

Intrapleural pressure

49. Which pressure is created by the elastic recoil of the lungs and chest wall?

Intrapleural pressure

19. Bicarbonate is an important buffer in blood and its concentration is regulated by the

Kidneys

50. Why are alveoli arranged in small grape-like clusters?

Maximize surface are and minimize thickness

31. What is the term for the volume of air moved into the lungs every minute?

Minute ventilation Ve= (TV x RR) Minute ventilation= Tidal Volume (TV) x Respiration Rate (RR) Respiration Rate (RR)= Number of breaths per minute

42. What is the most abundant gas in the air that we breathe?

Nitrogen

47. What is the primary driving force for the binding of oxygen to hemoglobin?

PO2

26. In a mixture of gases, the driving force for the movement of an individual gas within that mixture is ultimately the

Partial pressure of that gas

28. What is the function of ciliated cells in the conducting zone?

Propel mucus containing trapped particles toward the glottis

44. Which of the following specifically describes the movement of air into and out of the lungs?

Pulmonary ventilation

12. The intra-alveolar pressure is determined by what two factors?

Quantity of air in the alveolus and volume of the alveoli Intra alveolar pressure is the pressure of air within the alveoli.

41. Which of the following measurements cannot be determined by a spirometer?

Residual volume

22. The volume of air remaining in the lungs following a maximum expiration is called

Residual volume (averages 1200mL)

16. The presence of a negative intrapleural pressure at maximum expiration is responsible for which of the following?

Residual volume - the volume of air remaining in the lungs after a max expiration

9. Functional residual capacity is comprised of which of the following?

Residual volume and expiratory reserve volume only FRC= Functional residual capacity= ERV + RV = (average 2200 B/C average ERV is 1000mL and average RV is 1200mL) FRC Functional Residual Capacity is the volume of air remaining in the lungs after maximum expiration.

29. Movement of oxygen and carbon dioxide between alveoli and blood occurs by what process?

Simple diffusion

15. The muscles of respiration are

Skeletal muscles, innervated by the somatic nervous system Inspiration muscles- external intercostal muscles and diaphragm Expiratory muscles- internal intercostal muscles and abdominal muscles. External muscles contract and diaphragm contracts (inspiration) (expiration) external intercostals relax and internal intercostals and abdominals contract for active expiration only. When inspiratory muscles contract, the chest wall expands, causing the lungs to expand. Quiet expiration occurs passively by relaxation of the muscle of inspiration, which allows the lungs and chest wall to recoil in their original positions. Active expiration requires contraction of the muscles of expiration, while the muscles of inspiration relax.

40. What is rapid shallow breathing called?

Tachypnea

24. Gangrene is often caused by anaerobic bacteria which reside deep inside of tissues that lack adequate blood flow and therefore adequate oxygen supply. Many times, gangrene can be treated by putting the patient into a hyperbaric chamber. Which statement best describes why this type of therapy is effective?

The increased pressure drives more oxygen into the bloodstream and therefore, anaerobic bacteria cannot survive in the presence of oxygen.

34. What is the volume of air moved into and out of the lungs in a single breath during unforced breathing called?

Tidal Volume (TV)

33. What is the tidal volume + inspiratory reserve volume + expiratory reserve volume + residual volume called?

Total Lung Capacity (TLC)

21. The volume of air in the lungs following a maximum inspiration is called

Total lung capacity- the volume of air in the lungs at the end of a maximum inspiration. Sum of the tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume (TLC= Vt + IRV + ERV + RV) averages 5700mL. Total Lung Capacity (TLC): The residual volume (air you cannot expire) + vital capacity (total volume available for use) = total lung capacity. In other words, TLC is the total volume of the lungs! Inspiratory Reserve Volume (IRV): Total lung capacity minus the volume of air in the lung at the end of a normal inspiration. This means that we have a reserve volume that we can tap into as tidal volume increases with exercise or activity.

38. Which cells form the lung tissue component of the respiratory membrane?

Type I Alveolar cells - Epithelium

39. Which cells secrete surfactant?

Type II Alveolar cells

32. What is the tidal volume + inspiratory reserve volume + expiratory reserve volume called?

Vital Capacity (VC)

13. The maximum volume of air that can be expired following a maximum inspiration is called

Vital capacity (VC) - average 4500mL

21. During intense exercise, the metabolic activity of muscle causes ________ in the partial pressure of oxygen in the tissue, ________ the movement of oxygen into the tissue.

a decrease, facilitating

5. As oxygen binds to hemoglobin, the ________ of the hemoglobin molecule will change through a process of ________ such that the binding of oxygen is enhanced.

affinity : positive cooperativity

25. Hyperventilation will cause changes in PCO2 that are detected by the chemoreceptors which causes a(n)

decrease in breathing rate and depth of breathing.

4. As the lungs expand, intra-alveolar pressure ________ and air moves _______ the lungs.

decreases; into

23. Each ________ on the hemoglobin subunit is capable of binding an oxygen molecule, thereby allowing _________ oxygen to bind with one hemoglobin molecule.

heme, four

20. Chemoreceptors respond primarily to changes in PCO2 indirectly by its effect on

hydrogen ion concentration.

36. The presence of bicarbonate ions in the blood has an important direct effect, in addition to the transport of CO2, which involves

maintaining acid-base balance.

7. At rest, expiration is a(n) ________ process that involves _______.

passive, relaxation of the diaphragm and external intercostals

10. The compliance of the lungs can be determined by measuring the change in ________ for a given change in ________.

resistance, for a given change in

3. A(n) ________ is used clinically to measure lung volumes and rates of air flow.

spirometer