Gases in the Air and Breathing

Which of the following gases is most abundant in our air?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Argon

Which gas from the air is used up during respiration and burning?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Argon

Which gas in the air is used by plants in photosynthesis?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Argon

Which of these gases is least abundant in the air?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Argon

Which of these gases is transferred using alveoli to blood cells in our lungs?

• Oxygen

• Nitrogen

• Carbon Dioxide

• Argon

Which of the following organs is not used in breathing?

• Intercostal muscles

• Lungs

• Bladder

• Nose

If a candle is burned inside a glass or gas jar that is surrounded by water, what percentage of the gas jar should be filled with water once the candle goes out?

• 78%

• 20%

• 5%

• 0.04%

This organ is NOT used during the transport of oxygen in blood around the body.

• Heart

• Lung

• Large intestine

• Trachea

The percentage of nitrogen in inhaled air compared to exhaled air is:

• The same

• higher

• lower

• varies with altitude

The percentage of carbon dioxide in inhaled air compared with exhaled air is:

• the same

• higher

• lower

• varies with altitude