PSLE Science: Body Systems and Gas Exchange

What is the main topic discussed in the video?

• The water cycle

• Body systems and gas exchange

• Electric circuits

• Plant photosynthesis

What happens to the oxygen levels in a closed space with people inside?

• Oxygen is converted to nitrogen

• Oxygen levels increase

• Oxygen levels remain the same

• Oxygen levels decrease

How do carbon dioxide levels change in a closed environment with people?

• Carbon dioxide levels remain unchanged

• Carbon dioxide is converted to oxygen

• Carbon dioxide levels increase

• Carbon dioxide levels decrease

What happens to nitrogen levels in a closed space with people?

• Nitrogen levels remain unchanged

• Nitrogen is converted to carbon dioxide

• Nitrogen levels increase

• Nitrogen levels decrease

What change occurs to water vapor levels when people are in a closed environment?

• Water vapor levels remain the same

• Water vapor is converted to oxygen

• Water vapor levels decrease

• Water vapor levels increase