Danica builds a model of human lungs in biology class using a plastic bottle, scissors, two small balloons, one large balloon, a rubber band, and a y-tube. the large balloon on the bottom of the bottle represents a diaphragm, whereas the smaller balloons represent a pair of lungs. to represent lung function, danica gently moves the large balloon that is stretched across the bottom of the bottle up and down. as she pulls the large balloon down, the two small balloons inflate. as she pushes the large balloon up, the two small balloons deflate. danica wants to model a chest injury by making a hole in the bottle. which of the following will most likely happen if danica uses a pair of scissors to cut a small hole in the side of the plastic bottle?

When Danica makes a hole in the bottle -to model chest injury- the small balloons will no longer inflate and deflate when she moves the large balloon up and down.

Explanation:

The options for this question are:

In the model of human lungs, while the bottle was intact, the movement of the large balloon (diaphragm) down produced increased pressure - negative pressure - inside the bottle, allowing air to enter the small balloon (lung).

When the bottle is broken it loses the vacuum in it, which avoids the negative pressure and the air intake will not be to the small balloon but to the inside of the bottle. Consequently, the small balloon will remain deflated (no longer inflate and deflate when Danica moves the large balloon up and down).

In real life, a penetrating chest injury produces changes in intrathoracic pressure -becoming positive- and keeping the lung collapsed, with no entry or exit of air in it, which is called pneumothorax.

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