Inkpotamus

“There's no such thing as suction,”
The science teacher said,
Then she heard an interruption:
“You must be off your head!”

Her pupils looked quite unconvinced,
Their faces disbelieving,
The science teacher blushed and winced,
At the frowns she was receiving.

“Hang on,” said a boy, “I think,”
“Your statement has a flaw,
For when I suck upon my drink,
It pulls it up the straw!”

“It doesn’t pull, please understand,”
She continued with the lesson,
“Your diaphragm and chest expand,
To make the pressure lessen.”

“The drink is pushed right up the straw,
By the atmosphere that’s pressing,
Against what’s like an open door,
When your lungs are decompressing.”

“Suction is not pulling in,
It’s just less pushing out,
It’s the pressure in your lungs within,
Being less than that without.”

“If the pressure inside could drop too low,
Your body would implode,
Air pressure pushing at your guts,
Would push them through your nose.”