Biology-C2-Respiration

• All living things respire
• Things that respire/breathe


  • Humans
  • Animals
  • Plants
• Respiration


  • All living plants and animals respire
  • Animals respire using respiratory organs (lungs in humans)
  • During respiration, air enters the lungs (inhalation) and comes out (exhalation)

  
• Respiratory Gaseous Exchange


  1. Verify the presence of gaseous exchange

  2. Identify the exchanged gases using oximeter and lime water
• Aquatic Medium


  In water
• Aerial Medium


  In the air
• Aquatic animals take in (absorb) oxygen from the water
• Experiment without the goldfish


  The quantity of oxygen remained constant/the same

  
• Experiment with the goldfish

  The quantity of oxygen decreased with time

  
• At the beginning of the experiment, the concentration of oxygen is 9.2 mg/L in both the control experiment and the experiment with fish

  
• After 5 minutes, the concentration of oxygen is 8.8 mg/L in the enclosure with fish and 9.2 mg/L in the control experiment, enclosure without fish

  
• Lime water


  A solution used in experiments to test for the presence of carbon dioxide. In the presence of carbon dioxide, it becomes turbid (cloudy).

  
• The appearance of the lime water is clear and colorless in water (A) from the enclosure without fish. However, the appearance of the lime water is cloudy/turbid in water (B) from the enclosure with fish

  
• Aquatic animals release CO2 which makes the lime water turbid
• Specify


  Indicate + Justify
• The exchanged gases between the fish and water are oxygen and carbon dioxide, since after 5 minutes, the concentration of O2 has decreased 0.4 mg/L indicating an absorption of O2, and lime water turbidity indicates a release of CO2 by fish

  
• The setup without fish is the control one, it serves as a reference (comparison) and confirms that fish are consuming O2 during respiration

  
• Both terrestrial and aquatic animals absorb oxygen and release carbon dioxide during respiration
• Respiration is to absorb CO2 and release O2
• Lime water is turbid in the presence of carbon dioxide
• An experimental setup without a fish is a control set up

  
• An oximeter is an apparatus for measuring the concentration of oxygen in a medium

  
• After 10 minutes, in container A containing the germinating seeds, lime water became turbid and O2 concentration decreased from 21% to 19.6% indicating the release of CO2 and the absorption of O2 by these seeds
• Oxygen and carbon dioxide are the exchanged gases between the germinating seeds and air
• Deduce


  Draw using logical reasoning new information from given or existing information
• Respiration consists of the absorption of oxygen from the medium of the living thing (water or air) and the release of carbon dioxide
• The variation of the quantity of carbon dioxide with respect to time shows that the amount of CO2 increases from 30 mg/L at 1 min to 32.5 mg/L at 6 min, indicating that the goldfish releases CO2 into the water during respiration

  
• The control experiment (water without fish) is needed to validate the hypothesis, since it confirms that the fish releases CO2

  
• To identify the presence of CO2 in water, we take a small amount from the container where the fish was present, and we add it to a jar containing lime water. The lime water becomes turbid indicating the presence of CO2 in the water added to the container

  
• CO2

  For CO2
• O2

  For O2
• All living things need to breathe to survive
• Respiration


  The process of inhaling (taking in) oxygen & exhaling (releasing) carbon dioxide

  
• Aerial medium


  In the air
• Aquatic medium


  Under water
• Tests


  • Oximeter
  • Lime water
• Chapter 3: Respiration in Living Things
• Respiration


  1. Inhalation: air rich in oxygen enters the body

  2. Exhalation: air rich in carbon dioxide exits the body

  
• Organisms


  • Frogs
  • Horses
  • Humans
  • Insects
• Aerial pulmonary respiration


  • Through the lungs