Respiratory System

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Learning Intention: Science Understanding – “Cells are the basic units of living things and have specialised structures and functions. Multi-cellular organisms contain systems of organs that carry out specialised functions that enable them to survive and reproduce.”

Success Criteria:  Students will be able to identify the organs within the respiratory system and describe how it functions. They will understand how the respiratory, circulatory and digestive systems are connected and work together to deliver nutrients and oxygen and remove wastes from every cell within the human body.

So far we have learned about nutrition and the digestive system and how the circulatory system transports materials around the human body. Now we are going to investigate the respiratory system, which provides oxygen to every cell, to allow energy to be released from food. The respiratory system consists of the trachea, bronchus and lungs containing alveloi. There is an important muscle, called the diaphragm, that allows air to be drawn into the lungs and the carbon-dioxide-rich air to be expelled. Access the following sites and then answer the questions below:

  1. Label the diagram of the respiratory system, including the alveoli.
  2. What are the advantages of breathing through your nose?
  3. Why should you blow your nose when you have a cold, rather than sniffing?
  4. What is the function of the epiglottis and happens when you choke?
  5. Where do the respiratory and circulatory systems meet?
  6. Both systems have a large surface area – explain why.
  7. Breathing and respiration have different meanings – explain each.
  8. Both your breathing and heart rate increase during exercise – explain why.
  9. How do high altitudes affect your breathing and circulation? Why might athletes do high altitude training?

Circulatory System

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  • Science Understanding “Cells are the basic units of living things and have specialised structures and functions. Multi-cellular organisms contain systems of organs that carry out specialised functions that enable them to survive and reproduce.”
  • Science Inquiry Skills – “Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate.”

Learning Intention and Success Criteria: Students will be able to identify the structure and function of organs in the circulatory system and be able to name and describe the components of blood. Students will complete a labelled diagram of the heart and circulatory system and be able to describe how it works.

The Circulatory System is also called the “Cardiovascular System” and consists of the heart, arteries, veins, capillaries and the five litres of blood (approximately) that flows through this system.

1. Work your way through the National Geographic – Heart Interactive. Label the blank heart diagram with the names of each structure, including the atria, ventricles, aorta and valves.

2. Watch the National Geographic Video – Cardiovascular system and then colour the cardiovascular diagram showing oxygenated (red) and deoxygenated (blue) blood.

3. Access the Blood Buddies – the Australian Red Cross Blood Service website and find out how you are tested for your blood type. Do you know what blood group you belong to? Create a graph (bar graph or pie chart) showing the different blood groups:

  • O positive – 40%
  • O negative – 9 %
  • A positive – 31%
  • A negative – 7 %
  • B positive – 8%
  • B negative – 2%
  • AB positive – 2 %
  • AB negative – 1%

Other information:

Student graph showing percentages of each blood type from Australian Red Cross data using “Create-a-graph”.

Year 7 – Skin, Bone, Muscle and Nerves


Your body consists of different systems that work together to provide nutrients, remove wastes, allow you to move, grow and reproduce. This term we will be studying the skeletal, muscular and nervous systems as well as the skin. These systems consist of organs, which are made up of tissues, which are comprised of cells.

The “Cell Theory” states that:
“Cells” are the smallest unit of life.
All living organisms are composed of cells and their products
All cells arise from pre-exisiting cells.

These cells are made up of organelles (nuclei, mitochondria, chloroplasts, golgi complexes, ribosmoes etc.). Organelles are made up of compounds (molecules) which consist of atoms. Atoms are known as the smallest indivisible particles.

So skin is made up of specific types of cells, different to muscle cells, bone cells and nerve cells. These different types of cells are different sizes and shapes and contain different nunmbers of organelles (a red blood cell has no nucleus for example) because they perform different functions within the body. Draw up a table in your workbook (or on your netbook) with the four different systems and describe their structure (what they look like) and function (how they work). Draw an example of the four different cell types in these systems. Use your textbook and research using the internet to complete your table.

Your first experiment will be about the nervous system – “How Quickly can you Respond to a Stimulus?”. Draw up the table in your books (or your netbook) and record your results from the experiment described on page 285. Compare your average in your writing hand with your non-writing hand. Then use your mobile phone to send a text message or play a game on your ipod while doing the same test.
What do you notice about the results?
What does this suggest to you about using a phone or ipod while driving?
Then try the same type of test at “The Online Reaction Time Test” page. See if you can beat my average reaction time of 0.273 seconds! Let me know in the comments section what your average reaction time for each experiment was.