Page 122 - (DK) Danger! Open with Extreme Caution!

Signals from the eyes are picked up by the parts of the brain that register “fear,” which sets in motion the emergency response. Part of that response makes the pupils much wider, letting more light into the eyes to give a much clearer view of the approaching threat. Hypothalamus This small part of the brain commands the body’s emergency service. Once alerted to a threat, the hypothalamus sends out electrical signals. These instruct organs, especially

Eyes

wasps automatically triggers the body’s emergency
EMERGENCY SERVICE
service. This gears up the body into fight-or-flight
Like any other threat, an approaching swarm of
through the ANS (autonomic nervous system)
the brain’s hypothalamus. This sends signals,
mode—a response that is set in motion by
hotline, to target key body organs so that

the body is prepared for danger.

Bronchioles in Lungs These air passages branch out to every part of both lungs. At the end of each bronchiole, oxygen passes into the blood for delivery to the body’s cells, where it is used to release energy from glucose. In an emergency, bronchioles widen so that extra oxygen gets into the blood in order for the cells to generate more energy.

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