Ch7 Respiratory

13. Myoglobin

A compound similar to hemoglobin, but found in muscle tissue, that carries oxygen from the cell membrane to the mitochondria

19. Respiratory centers

Autonomic centers located in the medulla oblongata and pons that establish breathing rate and depth

5. Gas exchange between the air in the alveoli and the blood in the pulmonary capillaries occurs...

Gas exchange between the air in the alveoli and the blood in the pulmonary capillaries occurs across the respiratory membrane. It is the barrier that allows for the pressure gradients for the different gases.

inspiration is...

Inspiration is an active process involving the diaphragm and the external intercostal muscles. The ribs and sternum are moved by the external intercostal muscles. The ribs swing up and out in the sternum swings up and forward. At the same time, the diaphragm contracts, flattening down toward the abdomen. These actions expand the thoracic cage, increasing the volume inside the lungs. Increasing the volume allows the air to flow in and the air to fill more space. The pressure goes down and the atmospheric pressure is more outside of the body. Thus, the air outside comes inside the body. Expiration is relaxation of inspiratory muscles and elastic recoil of the lung tissue. The diaphragm returns to its normal upward arched position when relaxed. The external intercostal muscles relax, the ribs and sternum move back to the resting positions. Elastic nature of the lung tissue causes it to recoil to its resting size. This increases the pressure in the lungs in, and therefore, air is forced out of the lungs. During forced expiration, the internal intercostal muscles actively pull down the ribs; they're assisted by the latissimus dorsi and quadratus lumborum muscles. Contracting the abdomen muscles forces the diaphragm to accelerate towards its domed position. Some muscles and expiration also help return venous blood back to the heart.

4. Boyle's gas law

Law stating that a constant temperature, the number of gas molecules in a given volume depends on the pressure

9. Fick's law

Law stating that the net diffusion rate of a gas across the fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane, and inversely proportional to the thickness of the membrane

7.Oxygen is bonded to...

Oxygen is bonded to myoglobin it is only released when there is very low pressure in the muscle. CO2 exit the cells by simple diffusion because the pressure in the muscles is higher than the blood.

6. Oxygen is transported by...

Oxygen is transported by the blood either one to find a hemoglobin in the red blood cells or 2 dissolved in the blood plasma. Each molecule of hemoglobin can carry four molecules of oxygen. When oxygen binds to hemoglobin, it forms oxyhemoglobin. Carbon dioxide is carried in the blood as bicarbonate ions resulting from the dissociation of carbonic acid, dissolved in plasma, bound to hemoglobin called carbaminohemoglobin.

21. Respiratory pumps

Passive movement of blood through the central circulation as a function of pressure changes during breathing

5. Dalton's law

Principle stating that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of those individual gases

7. Expiration

Process by which air is forced out of the lungs through relaxation of the inspiratory muscles and elastic recoil of the lung tissue, which increase the pressure in the thorax

11. Inspiration

The active process involving the diaphragm and the external intercostal muscles that expands the thoracic dimensions and thus the lungs. The expansion decreases pressure in the lungs, allowing outside air to rush in

4.The air is composed of...

The air is composed of 79.04% nitrogen, 20.93% oxygen, and 0.03% carbon dioxide. At sea level, the atmospheric pressure is approximately 760 mm Hg. Thus if the total atmospheric pressure is 760 mmHg, then the partial pressure of nitrogen in air is 600.7 mmHg. Oxygen partial pressure is 159.1 mmHg. Carbon dioxide partial pressure is 0.2 mmHg. Differences in partial pressures of the gases in the alveoli and the gases in the blood create a pressure gradient across the respiratory membrane. This allows for gas exchange.

23. Tidal volume

The amount of air inspired or expired during a normal breathing cycle

18. Residual volume

The amount of air that cannot be exhaled from the lungs

2. Arterial-mixed venous oxygen difference

The difference in oxygen content between arterial and mixed venous blood, which reflects the amount of oxygen removed by the whole body

3. Arterial-venous oxygen difference

The difference in oxygen content between arterial and venous blood at the tissue level

12. Internal respiration

The exchange of gases between the blood and tissues

16. Pulmonary diffusion

The exchange of gases between the lungs and the blood

25. Vital capacity VC

The maximum volume of air expelled from the lungs after maximal inhalation

22. Spirometry

The measurement of lung volumes and capacities

20. Respiratory membrane

The membrane separating alveolar air and blood, composed of the alveolar wall, the capillary wall, in their basement membranes

8. Oxygen is bonded to...

The oxygen content in the arteries is 20 mL per 100 mL of blood. This value decreases to 15 - 16 mL of oxygen per 100 mL through the capillaries into the venous system at rest and to 5 mL during exercise. The difference in oxygen content between arterial and venous blood is referred to as the arterial-mixed venous oxygen difference. At rest, the tissues use 4-5 mL of oxygen per 100 mL of oxygen. During exercise tissues can use 15 - 16 mL per 100 mL of blood. This is to supply oxygen for the operation of the muscles.

15. Partial pressure

The pressure exerted by the an individual gas in a mixture of gases

8. External respiration

The process of breathing air into the lungs in the resulting exchange of gases between the alveoli and the capillary blood

14. Oxygen diffusion capacity

The rate at which oxygen diffuses from one place to another

9. The respiratory muscles are controlled by...

The respiratory muscles are controlled by the motor neurons, which are regulated by the respiratory centers in the brain stem. The centers establish the rate and depth of breathing by sending out periodic impulses to the respiratory muscles. The central chemoreceptors in the brain are stimulated by an increase in H+ ions in the cerebrospinal fluid. The blood-brain barrier is relatively impermeable to H+ ions or bicarbonate. However CO2 readily diffuse across the blood-brain barrier and then reacts to increase H ions. This, in turn, stimulates the inspiratory center, which then activates the neural circuitry to increase the rate and depth of respiration. This increasing respiration, in turn, increases the removal of carbon dioxide and H+. Pressure of CO2 appears to be the strongest stimulus for the regulation of breathing. When carbon dioxide levels become too high, carbonic acid forms, then quickly disassociates, giving off H+. If H+ accumulates, the blood becomes too acidic. Thus, an increased pressure of CO2 stimulates the inspiratory center to increase respiration - not to bring in more oxygen but to rid the body of excess carbon dioxide in limit further pH changes.

24. Total lung capacity TLC

The sum of vital capacity and residual volume

6. Dead space

The volume of air inhaled that does not take part in the gas exchange because it remains in the conducting airways

10. Henry's law

law stating that gases dissolve in liquids in proportion to their partial pressures, depending on their solubilities in the specific fluids and on the temperature

3. A spirometer...

measures the volumes of air inspired and expired in there for changes in lung volume. Total lung capacity is the sum of vital capacity and residual volume Vital capacity is the maximum volume of air expelled from the lungs after maximal inhalation. Tidal volume is the amount of air inspired or expired during a normal breathing cycle. The functional residual capacity is the volume of air remaining in the lungs after normal expiration. Residual volume is the amount of air that cannot be exhaled from the lungs.

17. Pulmonary ventilation

the movement of gases into and out of the lungs

1. Alveoli

the smallest respiratory unit where exchange of oxygen and carbon dioxide occurs