4.1 - Carbon Cycle & Water Cycle

• Why is recycling nutrients important for all living organisms?

  It provides the nutrients that living organisms use to grow and reproduce
• Water Cycle :

  1. Water from lakes, rivers, oceans, and the soil, evaporates into water vapour, and rises into the atmosphere.
  2. Water can also evaporate from plants in a process called transpiration.
  3. As the water vapour accumulates it can condense to form clouds.
  4. Later, the water will fall as rain, which we call precipitation.
  5. The water will then seep into the soil, flow into rivers or lakes, and be taken up by plants. 
  6. The whole cycle then repeats over and over. 
• Which statement about evaporation is correct?

  • Evaporation requires energy
  • Evaporation is a passive process
  • Evaporation releases energy
  • Evaporation requires energy
  • Evaporation is the process of liquid water turning to water vapour. This change in state requires energy
• What happens to water during condensation?

  Water vapour turns into liquid water
• Which process in the carbon cycle removes carbon dioxide from the atmosphere?

  Photosynthesis 
• Which three processes in the carbon cycle release carbon dioxide into the atmosphere?

  • Combustion
  • Respiration 
  • Decomposition
• Which carbon-containing compound do plants produce during photosynthesis?

  Glucose 
• Why is it important that there is carbon dioxide in the atmosphere?

  Carbon dioxide is needed for photosynthesis in plants
• Which organisms decompose dead organic matter?

  • Fungi
  • Bacteria
• How long has life on Earth existed?

  Billions of years
• Why has life on Earth been possible?

  Because it recycles molecules and atoms
• What are some individual atoms recycled in life on Earth?

  Nitrogen, phosphorus, and carbon
• How many atoms are estimated to be in a human body?

  Six octillion atoms
• Where do the atoms in our bodies come from?

  Oceans, volcanoes, other animals, and humans
• What are the two cycles covered in the study material?

  • Water cycle
  • Carbon cycle
• What is the first step in the water cycle?

  • Energy from the sun causes evaporation
• What types of water can evaporate in the water cycle?

  Water from lakes, oceans, rivers, and land
• What is transpiration in the water cycle?

  Evaporation of water from plant leaves
• What happens to water vapor as it accumulates in the sky?

  It condenses into clouds
• What is the term for water falling back to Earth?

  Precipitation
• After precipitation, what can happen to the water?

  It can seep into soil, flow into rivers, or be taken up by plants
• What are the main stores of carbon in the carbon cycle?

  • Atmosphere (as carbon dioxide)
  • Plants (in biological molecules)
  • Soil (with microorganisms)
  • Fossil fuels (underground)
  • Animals (in biological molecules)
• What is the most important process in the carbon cycle?

  Photosynthesis
• What do plants and algae do during photosynthesis?

  They convert carbon dioxide into glucose
• What happens to carbon in plants after photosynthesis?

  It can be released by respiration or passed to animals
• What occurs when organisms die in the carbon cycle?

  They can be decayed or converted into fossil fuels
• What happens during microbial respiration of decayed organisms?

  Carbon is released as carbon dioxide
• What can happen to organisms that avoid decay?

  They may become fossil fuels like oil or coal
• How do humans contribute to the carbon cycle?

  By burning fossil fuels to produce carbon dioxide
• What is an additional process that can be included in the carbon cycle?

  Burning of plants or biofuels
• What are the key processes in the carbon cycle?

  1. Photosynthesis
  2. Respiration
  3. Decay by microorganisms
  4. Formation of fossil fuels
  5. Burning of fossil fuels