Page 8 - 新思维科学学生用书8 样章

1.1 The human respiratory system

Why we need oxygen

You may remember that one of the characteristics shared
by all living things is respiration. Respiration is a series
of chemical reactions that happens inside every living

cell.

The kind of respiration that usually happens inside our
cells is called aerobic respiration. Aerobic respiration
uses oxygen. The cells produce carbon dioxide as a waste
product.

The air around you contains oxygen. When you breathe,

you take air into your lungs. Some of the oxygen from
the air goes into your blood. The blood delivers the In this model of the human body, the lungs
oxygen to every cell in your body, so that the cells can are shown in orange
use it for respiration. The blood collects the waste

carbon dioxide from the cells, and takes it back to your lungs.

The organs that help you to take oxygen out of the air, and
get rid of carbon dioxide, make up the respiratory system.

Can you name any of the other organs shown in the
picture on the right?

The structure of the human entrance to nose
respiratory system entrance to mouth
voicebox (larynx)
This is a diagram of the human windpipe (trachea)
respiratory system. The white
spaces in this diagram are the rings of cartilage
‘tubes’ (bronchi and bronchioles) lung

that air moves through, bronchiole
as it goes into and out of bronchus (plural: bronchi)
your lungs. air sacs
rib bone
muscles between ribs
(intercostal muscles)
diaphragm

The human respiratory system

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