These flexible and pliable bands vibrate against each other, producing sound when air is expelled past them through the glottis.
As the bronchial tubes divide and subdivide, the walls of the two bronchi become thinner and there are no rings of cartilage.
The air in the alveoli and the blood in the capillaries exchange gasses.
The mechanisms used by mammals and birds to inflate their lungs are compared.
The lungs are connected to the rest of the body.
CO2 leaves the blood into the lungs while Oxygen moves into the blood.
Terrestrial animals move air into and out of their lungs.
Amphibians use positive pressure to get air into their lungs.
The floor of the mouth rises when the mouth and nostrils are closed.
Animals use positive and negative pressure to move air into and out of their lungs.
Boyle's Law states that at a constant temperature the pressure of a given quantity of gas is proportional to its volume.
When the sides of the container move outward, air pressure decreases inside the container and air moves in, just as air automatically enters the lungs when the rib cage moves up and out.
Air flows out of the container if the sides are pressed inward.
When the rib cage moves down, air exits the lungs.
If we want, forced expiration can happen.
When the sides of a container move outward, the volume of the container increases and the air pressure decreases.
Similar to moving the sides of the container inward, increased air pressure in the lungs causes air to flow out during exhalation.
mammals have a rib cage and a diaphragm, but reptile have jointed ribs that can be raised to expand the lungs.
In mammals and reptiles, inspiration is the active phase of breathing.
Air is drawn into the lungs during inspiration.
The lung positions and pressures are back to where they were before.
The air is forced out.
In mammals, the rib cage moves down and the diaphragm relaxes.
The passive phase of breathing in mammals and reptiles is called expiration.
Air flows out of the lungs during expiration due to increased pressure.
The lungs of salamanders, lizards, and mammals are not completely emptied during each breathing cycle.
The air entering mixes with used air in the lungs.
This decreases gas-exchange efficiency and helps conserve water.
Incoming air goes past the lungs to a set of air sacs.
Fresh air doesn't mix with used air in the lungs of birds, which improves gas-exchange efficiency.
Birds have air sacs in their lungs.
Birds have a oneway mechanism of ventilating their lungs.
Adults have a breathing rate of 12 to 20 per minute.
The center stops sending signals to the rib cage.
The breathing rate can be changed by stimulation of the intercostal muscles.
The respiratory center's activity can be influenced by both nervous and chemical inputs.
The nerve impulses that travel from the inflated lungs to the respiratory center are initiated by stretch receptors in the alveolar walls.
The respiratory center sends nerve impulses.
The respiratory center is sensitive to the levels of H+).
When carbon dioxide enters the blood, it reacts with water.
The breathing rate is regulated by CO2 in this way.
The respiratory center increases the rate and depth of breathing when the pH and hydrogen ion levels go down.
Respiration includes the exchange of gases in our lungs, as well as the exchange of gases in the tissues.
The movement of gases into and out of blood vessels in the lungs and tissues is governed by the principles of diffusion.
Oxygen will diffuse from the higher to the lower pressure if the partial pressure is different.
Carbon dioxide diffuses from the higher to the lower partial pressure.
The alveoli of the lungs have a higher Page 664 PO2 and a lower PCO2 than the blood in pulmonary capillaries, and this accounts for the exchange of gases in the lungs.
When blood reaches the tissues, cellular respiration in cells causes the interstitial fluid to have a lower PO2 and a higher PCO2 than the blood in the systemic capillaries, and this accounts for the exchange of gases in the tissues.
The transport of O2 and CO2 is different in external respiration than it is in internal inspiration.