The respiratory system is another one of our body systems. It is very important as here our body produces the energy which fuels all our daily activities. Remember respiration is a chemical reaction. The equation for respiration is shown below:
Below is a Word document with a diagram of the respiratory system as well as the lungs. Feel free to print and paste the second diagram into your books. You should have already drawn the diagram of the respiratory system and therefore can use this diagram as a reference guide.
Worksheet & Handout
I am attaching the worksheet which we have done in class today, feel free to do the worksheet and I am also willing to correct them and provide feedback to you all.
This is not a course work exam but will greatly help in your end of term exams. I am also attaching a handout on the respiratory system which contains additional information to what has been done in class.
Testing CO2 in Inhaled & Exhaled Air
Carbon dioxide can be determined as it turns lime water milky. You all have the diagram of the experiment which should be in your books by now :)
Exhaled air has more CO2 because when gaseous exchange occurs, CO2 is the waste product which is given off so therefore, there will be more in exhaled air.
Here is the video which we have looked at in class.
What does it mean to breathe?
When we breathe a mechanical process occurs, it is not a chemical reaction. There are changes which occur physically in our body which causes breathing.
Breathing can be broken up into a two step process:
Both inhalation and exhalation require different changes in our body. Lets look at the diagram below:
1. The diaphragm contracts (flattens)
2. This causes the ribs to use upwards and outwards
3. This increases the volume of the thorax. The pressure inside of the lungs decreases and this pulls on the lungs and causes it to expand.
4. Air is therefore, sucked into the lungs
Breathing out/ Exhalation/ Expiration
1. The diaphragm relaxes (bulges upwards)
2. The ribs move downwards and inwards
3. This decreases the volume of the thorax. The pressure inside your thorax increases and this squeezes the lungs.
4. Air id therefore forced out of the lungs
The Bell Jar Model of the Lungs
In class we briefly went through the bell jar model, I did not get the bell jar from the school to show you all but I'm sure that the video will help you to understand more about the bell jar. In previous lessons which I have taught on breathing I have had the students make a bell jar model and if we weren't rushed for time I would also have you all do the same. It is really a great way to help you in understanding breathing. The video below will help you to understand more about the bell jar model and its demonstration of breathing. It is also super easy to make!