Misconceptions breathing

You begin breathing 100% oxygen through a mask.

While you breathe from the mask, the amount of carbon dioxide in your lungs:

• Increases

• Decreases

• Stay the same

Your classmate is late for the biology test and she runs op three stairs to the biology classroom. When she arrives, you notice that her breathing frequency is increased. At the same time, you note that her depth of breathing (how much she takes in with each breath) is:

• Greater than normal

• Less than normal

• Unchanged

Why do we breathe?

Your vital capacity is the amount of air breathed out after taking a deep breath in. What happens to your vital capacity during a run of half an hour?

• It increases

• It decreases

• It stays the same

An experiment investigates the composition of the air a person breathes in and out. The composition of the air a test person breathes in is:

79% nitrogen

21% oxygen

0,04% carbon dioxide.

 

1. What will be the composition of the air this test person breathes out (2p)?

• 75% nitrogen, 21% oxygen, 4% carbon dioxide

• 79% nitrogen, 0% oxygen, 21% carbon dioxide

• 79% nitrogen, 16% oxygen, 4% carbon dioxide

• 83% nitrogen, 16% oxygen, 0.04% carbon dioxide

Put in the correct order.

i. Volume of chest cavity and lungs increase

ii. Intercostal muscles and diaphragm contract

iii. Air pressure is higher than lung pressure, so air flows in

iv. Air pressure in lungs decrease

• ii - i - iv - iii

• i - ii - iv - iii

• iii - iv - i - ii

• ii - iii - iv - i

Do plants breathe? Why or why not?

After breathing out, the air pressure in the lungs increases

• True

• False

Your lungs consist of muscle tissue

• True

• False

Lungs passively take in air

• True

• False