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Speaker 1: Welcome to Brainstuff from house stuff works dot com where

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Speaker 1: smart happens. Hi, I'm brain with today's question, how do

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Speaker 1: flies and other insects for that matter, breathe? Insects breathe

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Speaker 1: in a way that's very different from us. Instead of

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Speaker 1: having a central place to gather oxygen like human lungs

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Speaker 1: and a transport system like our heart and blood to

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Speaker 1: deliver the oxygen to all of the cells of the body,

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Speaker 1: insects have a system of fine branching tubes called a

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Speaker 1: tracheal system that's spread all over their bodies. Imagine that

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Speaker 1: you are an oxygen molecule in the atmosphere and you're

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Speaker 1: about to be breathed by an insect. You enter a

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Speaker 1: tiny hole on the insects thorax or abdomen, called a spirical.

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Speaker 1: The spircle is the opening of a long tube called

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Speaker 1: a trachea. You proceed down this tube, which is long,

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Speaker 1: air filled and branching. You continue to move through the

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Speaker 1: branches until you reach a tiny fluid filled dead end

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Speaker 1: called a tracheole. You dissolve into the fluid, and from

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Speaker 1: the fluid you diffuse or move across the wall of

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Speaker 1: the tracheol into an insects cell such as a muscle cell.

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Speaker 1: The movement of air through the tracheal system of most

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Speaker 1: insects relies solely on diffusion. Because most insects rely on diffusion,

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Speaker 1: which occurs best over small distances, they cannot get very large.

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Speaker 1: You'll not see huge ants as biggest buildings like in

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Speaker 1: the movie Them, because enough air could not diffuse that

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Speaker 1: far into their bodies to keep their cells alive. However,

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Speaker 1: some larger insects can use their abdominal muscles to force

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Speaker 1: air in and out of the tracheal system in a

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Speaker 1: limited way. So with this system in mind, it would

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Speaker 1: be difficult to stray angle a bug. However, if the

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Speaker 1: tracheal system fills with water, it takes much longer for

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Speaker 1: air to diffuse through the system. Therefore, an insect can

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Speaker 1: drown fairly easily for more illness and thousands of other topics.

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Speaker 1: to check out the brain stuff blog on the how

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