Respiratory

A red blood cell arrives in the ALVEOLUS where it is exposed to a P(O₂) of 104 mm Hg.

1 (alveolus)

Blood enters the pulmonary vein with close to 100% of the binding sites for oxygen saturated.

2 (100%)

Arriving at the arterial end of the tissue capillaries, the blood P(O₂) is 95 mm Hg.

3 (95 mmHg)

As RBCs pass through the systemic capillaries they experience oxygen unloading and increasing carbonic acid conversion.

4 (systemic capillaries)

After passing through the systemic capillary, 75% of the binding sites for oxygen are now bound with oxygen.

5 (75%)

Returning to the inferior vena cava, the blood is known to have a P(CO₂) of 45 mm Hg.

6 (45 mmHg)

Passing through the pulmonary artery, the P(O₂) is approximately 40 mm Hg.

7 (40 mmHg)

Place the items in the correct sequence for the process that occurs as blood moves through systemic capillaries and CO2 moves into the blood plasma.

Carbon dioxide (CO₂) diffuses into an erythrocyte, CO₂ is converted into H₂CO₃ by carbonic anhydrase, Carbonic acid splits into bicarbonate and hydrogen ions, HCO₃⁻ exits from the erythrocyte and chloride ions go into the erythrocyte to equalize the charges

Place the items in order from superficial to deep.

Elastic connective tissue, hyaline cartilage, areolar connective tissue, pseudostratified ciliated columnar epithelium

As the diaphragm relaxes, it is depressed (moves inferiorly).

False

Bronchioles have a proportionately thicker layer of smooth muscle than bronchi and contraction of this smooth muscle narrows the diameter of the bronchiole, referred to as bronchodilation.

False

The vestibular folds ("false vocal cords") assist the true vocal cords in sound production.

False

When the ventral respiratory group is activated, impulses are subsequently relayed to the dorsal respiratory group, resulting in a change in the rhythm and force of breathing.

False

Expiratory Reserve Volume + Residual Volume = _______ Capacity.

Functional residual

The trachea bifurcates at the level of the sternal angle (where the manubrium and body of the sternum articulate) into the right and left

Main bronchi

Airflow is a function of what two factors?

Pressure gradient and resistance

Place the respiratory structures below in the order that air would pass through them as it moves from the outside to the inside of the body.

Primary bronchus, secondary bronchus, tertiary bronchus, terminal bronchioles, respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli

Components of the respiratory mucous membrane include all of these EXCEPT:

Smooth muscle

The right lung has ________ lobes, and the left lung has ________ lobes.

Three, two

A healthy person should be able to expel 75-85% of the vital capacity in 1 second.

True

Cells typically produce about 200 mL/min of carbon dioxide as a waste product during cellular respiration.

True

During exercise, both oxygen consumption and carbon dioxide production increase in response to elevated rates of cellular respiration but blood P(O2) and P(CO2) levels remain relatively the same.

True

Oxygen diffuses across the respiratory membrane from the alveoli into the capillaries because of the P(O2) partial pressure gradient.

True

The P(O2) is lower in the alveoli than it is in the atmosphere, and the P(CO2) is higher in the alveoli than it is in the atmosphere.

True

The gas exchange surfaces of the lungs are part of the pulmonary circulation, while the bronchial circulation is part of the systemic circulation.

True

The partial pressure of each gas in the cells remains relatively constant because the continuous delivery of oxygen and removal of carbon dioxide corresponds with the amounts associated with cellular respiration.

True

The rate and depth of breathing influences the blood levels of oxygen (O2), carbon dioxide (CO2), hydrogen ions (H+), and also influences the venous return of blood and lymph due to changes in compression within the thoracic cavity that occur during breathing.

True

The respiratory membrane is only 0.5 micrometer thick and consists of an alveolar epithelium and its basement membrane, and a capillary endothelium and its basement membrane.

True

Total lung capacity can be calculated as: vital capacity + residual volume.

True

When partial pressures for a given gas are equal between the capillaries and the tissue fluids, no net movement of that gas occurs.

True

You cannot consciously hold your breath long enough to die.

True

The smallest respiratory bronchioles subdivide into thin airways called

alveolar ducts

The largest percentage of carbon dioxide is transported in the blood

as bicarbonate dissolved in the plasma.

The partial pressures of gases in cells of systemic tissues result from

cellular respiration

During alveolar gas exchange, blood P(CO2)

decreases from 45 to 40 mm Hg.

A condition called _______ is when blood P(CO2) decreases below normal levels.

hypocapnia

The pleural cavity

is a potential space that contains a lubricating fluid that allows the visceral and parietal pleura to slide by each other easily.

The amount of air that is moved between the atmosphere and alveoli in 1 minute is

pulmonary ventilation.

Change in the _______ of breathing is accomplished by altering the amount of time spent in both inspiration and expiration, whereas altering the _______ of breathing is accomplished through stimulation of accessory muscles, which results in greater thoracic volume changes.

rate, depth

During lung inflation

the lungs cling to the internal surface of the chest wall as it expands.