https://padlet.com/ilikestar223/2kugo6rvfpqu explanation of ventilation en-us 2017-03-17 00:44:55 UTC 2025-12-18 15:11:15 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Planets.png ilikestar223 https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162145416 -when you breath in movements of your diaphragm and ribcage move the chest cavity and pull on the lungs so they occupy a larger volume. This decrease the air pressure inside the lungs to below the pressure of atmospheric air so that air moves in through your nose/mouth
Summary: ventilation will change the volume and pressure inside the chest because of the movements of the diaphragm and ribcage.
KW: the diaphragm is the sheet of fibrous tissue and muscle that separate the thorax form abdomen.
its movements up and down changes the volume of the lungs to move air when you breath out and in.
Key points: the lungs are elastic organs found inside the chest and are surrounded and protected by the ribs and the sternum]]> 2017-03-23 14:33:07 UTC https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162145416 ilikestar223 https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162160446 -when you breath out, the diaphragm and intercostal muscles relax and this causes the chest capacity to decrease in volume. the air pressure in the lungs increases to above the atmospheric pressure so air is forced out. 
Summary: organs that control the changing of ventilation are intercostal and diaphragm. 
KW: the intercostal muscles between the ribs move the ribs during breathing, especially during deep breathing.
Key points: the process of gas exchange are -----
air enters the mouth or nose and passes through the throat to the larynx.
it then enters the trachea, which connects the throat to the lungs.
it branches to form two bronchi which enter each lung.
these continue to divide to form many small bronchioles, which end in tiny air sacs called alveoli. 
gas exchange will take place.

the characteristic of alveoli
large number 
huge surface area for diffusion
each alveoli is surrounded by a network of blood capillaries for efficient gas exchange into and out of the blood
thin walls made of a single layer of cells
short distance of diffusion
they are moist so oxygen dissolve in this watery fluid before diffusing through the walls into blood]]> 2017-03-23 15:08:27 UTC https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162160446 ilikestar223 https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162171399 1)the external intercostal muscles contract and the internal intercostals muscles relax, raising the ribs upwards and outwards.
2)at the same time, the diaphragm contracts and fattens.
3)both of these actions increase the volume inside the thorax, causing the pressure inside the thorax to decrease
4) since atmospheric pressure is greater, air moves into the lungs and they inflate.]]> 2017-03-23 15:33:44 UTC https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162171399 ilikestar223 https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162175533 1)the internal intercostal muscles contract and the external intercostal muscles relax.
2) the movements of muscles lower the ribs downward and inwards.
3)the muscle in the diaphragm relaxes and it bulges up due to pressure from the organ below like the liver and stomach , and contraction of the abdominal muscles.
4) muscles relaxing decrease the volume inside the thorax after that the pressure inside the thorax also decreases.
5) elastic recoil of the alveoli helps to force air out of the lungs.

]]> 2017-03-23 15:43:51 UTC https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162175533 ilikestar223 https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162180220 2017-03-23 15:55:21 UTC https://padlet.com/ilikestar223/2kugo6rvfpqu/wish/162180220