Page 5 - 新思维科学学生用书8 样章

How to use this bookHow to use this book

How to use this book

1 Respiration
1 Respiration

This book contains lots of different features that will help your learning. These are explained below.
1.1 The human respiratory system
1.1 The human respiratory system
This list sets out what you will learn in each topic. You can In this topic you will:
learn the names of
• In this topic you will: the different parts of the human
use these points to identify the important topics for the • • respiratory system
learn the names of the different parts of the human
observe carefully, and record your observations, as the
respiratory system
observe carefully, and record your observations, as the
lesson. 1 Respiration • structure of lungs is demonstrated.
structure of lungs is demonstrated.
Getting started 1.1 The human respiratory system Key words
Getting started
Key words
Respiration is one of the characteristics of living things. aerobic respiration
1.1 The human respiratory system
This contains questions or activities to help find Continued With a partner, decide which statement in each pair is air sacs
Respiration is one of the characteristics of living things.
aerobic respiration
correct.
With a partner, decide which statement in each pair is
air sacs
out what you know already about this topic. 2 Touch the lungs. Be ready to share your ideas. Respiration only bronchioles
correct.
bronchus
bronchioles
In this topic you will:
What do they feel like when you push them? Can you suggest why they feel like
Be ready to share your ideas.
Respiration happens
bronchus
• learn the names of the different parts of the human First pair: inside all the cells in or happens in cells cartilage
this? (Look at the diagram of the human respiratory system to help you.)
Respiration only
Respiration happens
cartilage
respiratory system 3 Look at the tube that carries air down into the lungs. or happens in cells larynx
your body.
in your lungs.
First pair:
inside all the cells in
Key words are highlighted and defined in the a What is the name of this tube? your body.ases Respiration uses respiration
•
observe carefully, and record your observations, as the
larynx
Second
Respiration rele
in your lungs.
structure of lungs is demonstrated. b Feel the tube. What does it feel like? or Respiration uses respiratory system
respiration
pair:
energy from food.
up energy.
Second
Respiration releases
text when they first appear in the book. You c Follow the tube towards the lungs. Can you find where it divides into two? trachea
or
respiratory system
pair:
energy from food.
up energy.
Respiration
What are the names of these two tubes?
Respiration happens
trachea
Third pair:
or
Getting started d Now look at the top of the big tube, where it is wider. happens in animals vocal cords
Key words
Respiration
in all living things.
will also find definitions of all these words What is the name of this wide part? What is its function? happens in animals voicebox
Respiration happens
vocal cords
but not plants.
Third pair:
or
Respiration is one of the characteristics of living things.
aerobic respiration
in all living things.
voicebox
With a partner, decide which statement in each pair is air sacs but not plants. windpipe
in the Glossary and Index at the back of windpipe
correct.
bronchioles
Be ready to share your ideas. The diagram of the respiratory system includes a lot of new words.
bronchus
this book. Respiration happens How are you going to learn this diagram and all of its labels?
Respiration only
cartilage
happens in cells
First pair: inside all the cells in or Remember that, in a test, the diagram might not be exactly the
your body. same as this one. larynx
in your lungs.
respiration
Second Respiration releases or Respiration uses
up energy.
energy from food.
pair:
You will have the opportunity to practise and Activity 1.1.1 respiratory system
trachea
Respiration
Respiration happens or What does the larynx do?
vocal cords
Hold the fingertips of one hand against your larynx (voicebox).
happens in animals
Third pair:
develop the new skills and knowledge that voicebox
in all living things.
but not plants.
Keep your lips together, and make a loud humming sound.
windpipe
you learn in each topic. Activities will involve Can you feel the larynx vibrating?
Your larynx contains your vocal cords. These are bands of muscle that stretch across
answering questions or completing tasks. your larynx. You can think of them as being like guitar strings. When your vocal cords
vibrate, they make a sound.
Now make a higher-pitched humming sound. Then try a really deep pitched sound.
Can you feel the larynx changing when you make the different sounds?
1.2 Gas exchange
Summary checklist
Think like a scientist
I can name the parts of the respiratory system, and identify them on a diagram.
Why are air sacs so small?
I can list the organs that air passes through, as it moves into and out of the
In this activity, you will use some agar jelly to represent the lungs, and some coloured
lungs.
liquid to represent oxygen in the air.
This provides an opportunity for you to You will need: 9
• two Petri dishes filled with agar jelly
practise and develop scientific enquiry • two cork-borers, one with a diameter of 10 mm and the other with a
diameter of 5 mm
• some coloured dye
skills with a partner or in groups • a dropper pipette
Method
1 Use the larger cork-borer to make eight holes in the jelly
in one of the dishes. Space the holes evenly in the dish.
2 Now use the smaller cork-borer to make 32 holes in the
jelly in the other dish. Try to space the holes evenly in the
dish.
3 Using the dropper pipette, carefully fill each hole in
both dishes with the coloured dye. Try to put the same
quantity of dye into each hole. It’s really important not to
get any dye on the jelly!
4 4 Leave both dishes for at least 15 minutes.
Predict what you think will happen.
5
6 After 15 minutes (or a little bit longer if things are
happening slowly) record your observations.
Questions
1 The holes that you made in the jelly represent the air sacs in the lungs. The
coloured dye represents oxygen in the air sacs. The holes in the jelly are an
analogy for the air sacs, and the dye is an analogy for oxygen.
Explain how your observations help to show what happens to oxygen in the lungs.
2 The total volume of the 32 small holes is the same as the total volume of the
eight large holes. Use your observations to suggest why it is better to have a lot
of very small air sacs in the lungs, rather than just a few large ones.
3 Do you think that the agar jelly with holes is a good model for what happens in
the lungs? Explain your answer.
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