Thursday, July 12, 2012

Breathing System

How is air brought to lungs?

The job of the breathing system is to continually move air into the lungs and then move it out again. This is brought about by movement of the ribcage which we feel, and by movements of the diaphragm which unfortunately we cannot feel nor see.
When we breathe, our ribs move up and out, and the muscles of the diaphragm contracts so it flattens from its normal domed shape thus pulls air into the lungs. However, when we breathe out what happens is that the ribs move in and down and the diaphragm returns back to its domed  shape, forcing air outside of the lungs.


This movement of air in and out of the body is known as ventilation 


Ventilation as part of the breathing system



The breathing movements are brought about by 
two different sets of muscles which change the pressure in the chest cavity. The intercorsal muscles between the ribs contracts pulling them upward and outward at the same time as the diaphragm muscles contract to flatten the diaphragm. These two movements increase the volume of the thorax and because the same amend of gas is now inside a much bigger space, the pressure inside the chest. This in return means the pressure inside chest is lower than the air outside therefore as a consequence, air moves into the lungs. Then, both the intercorsal and diaphragm muscles relax, the ribs drop and diaphragm domes up. The volume of the thorax is decreased and so the pressure inside the chest increases causing air to be squeezed and forced outside the lungs.


Questions:


1- How are the lungs adapted to allow gas exchange to take place as effective as possible?

2- What is the difference in composition between inspired and expired air? 

3- Explain fully how air is moved in and out of the lungs in human’s respiratory system?


References,



- Fullick, Ann (2001). Biology for AQA. Chicago: Heinemann Educational.


- Brain, J. D. (2006, August). The merck manual home health handbook. Retrieved from http://www.merckmanuals.com/home/lung_and_airway_disorders/biology_of_the_lungs_and_airways/exchanging_oxygen_and_carbon_dioxide.html


- Tamarakin, D. (2011, October 9). Stcc foundation press. Retrieved from http://faculty.stcc.edu/AandP/AP/AP2pages/Units21to23/respiration/alveolar.htm



- Peter. (2012). Anaerobic respiration articles. Retrieved from http://www.anaerobicrespiration.net/general/simple-definition-of-aerobic-and-anaerobic-respirations/

3 comments:

  1. This comment has been removed by the author.

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  2. 1)The alveoli give the lungs a large surface area for absorbing oxygen and excreting carbon dioxide. Furthermore the alveoli have thin walls so that gasses diffuse easily across them. Finally the cappliaries which have thin walls make it so that substances can easily pass into and out of the blood.

    2)Inhaled air contains more oxygen used to create energy and less carbon dioxide than exhaled air which contains more carbon dioxide produced as a waste product of energy production less oxygen as it has been used in respiration.

    3)The respiratory system is made up of the organs in your body that help you to breathe. Remember, that Respiration = Breathing. The goal of breathing is to deliver oxygen to the body and to take away carbon dioxide. The lungs are the main organs of the respiratory system. In the lungs oxygen is taken into the body and carbon dioxide is breathed out. The red blood cells are responsible for picking up the oxygen in the lungs and carrying the oxygen to all the body cells that need it. The red blood cells drop off the oxygen to the body cells, then pick up the carbon dioxide which is a waste gas product produced by our cells. The red blood cells transport the carbon dioxide back to the lungs and we breathe it out when we exhale.

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  3. 1) air is moved in and out of the lungs in human’s respiratory system by two different sets of muscles which change the pressure in the chest cavity. The intercorsal muscles between the ribs contracts pulling them upward and outward at the same time as the diaphragm muscles contract to flatten the diaphragm. These two movements increase the volume of the thorax and because the same amend of gas is now inside a much bigger space, the pressure inside the chest. This in return means the pressure inside chest is lower than the air outside therefore as a consequence, air moves into the lungs. Then, both the intercorsal and diaphragm muscles relax, the ribs drop and diaphragm domes up. The volume of the thorax is decreased and so the pressure inside the chest increases causing air to be squeezed and forced outside the lungs.


    2) The lungs adapted to allow gas exchange to take place as effective as possible by the ribs movement up and out, and the muscles of the diaphragm contracts so it flattens from its normal domed shape thus pulls air into the lungs. However, when we breathe out what happens is that the ribs move in and down and the diaphragm returns back to its domed shape, forcing air outside of the lungs.


    3) The inspired air is composed of O2 and the expired air of CO2

    ReplyDelete