Page 50 - Science Course 2 (Book 1)

Mo2-L3b: How are Nutrients Transported Around the Body?

Circulation
Mo2-L3b How are Nutrients Transported
Around the Body? Oxygen in the alveoli enters the capillaries.
KEY CONCEPTS:
1. How do nutrients travel through the body? The blood inside capillaries transports oxygen to the
rest of the body.
Let’s Begin

Respiration
The respiratory system exchanges gases between
the body and the environment.

The heart, blood, and blood vessels make up the
circulatory system which transports nutrients, gases,
wastes, and other substances through the body.

When you inhale, air enters the nostrils and passes
through the pharynx to the trachea.

Inhaling and exhaling require the movement of
a muscle under the lungs called the diaphragm.

The trachea, or windpipe, connects the pharynx to
the bronchi.

There are two bronchi; one enters the left lung and
one enters the right lung.
Blood enters the
The bronchi divide into smaller tubes that end in tiny heart through two
groups of cells called alveoli. upper chambers
called atria
The alveoli are surrounded by blood vessels called (singular, atrium)
capillaries.

Bronchioles
Trachea

Capillary
Bronchi
Blood leaves the
heart through two
lower chambers
called ventricles

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