Surface area to volume ratio

• Why can single-celled bacteria rely on diffusion?

  They have a high surface area to volume ratio
• What do large multicellular organisms require for substance exchange?

  Specialized exchange surfaces and transport systems
• What resources do single-celled organisms need to absorb?

  Oxygen, glucose, and amino acids
• What waste product do single-celled organisms need to eliminate?

  Carbon dioxide
• How does surface area to volume ratio change as organisms grow larger?

  It decreases as organisms get larger
• How do you calculate the surface area of a cube?

  • Calculate area of one face
  • Multiply by six (for six faces)
• What is the surface area of a 1 cm cube?

  6 square centimeters
• What is the volume of a 1 cm cube?

  1 cubic centimeter
• What is the surface area to volume ratio of a 1 cm cube?

  6 to 1
• What is the surface area of a medium cube with a volume of 8 cubic centimeters?

  24 square centimeters
• What is the volume of a medium cube with a surface area of 24 square centimeters?

  8 cubic centimeters
• What is the surface area to volume ratio of the medium cube?

  3 to 1
• What is the surface area of the largest cube with a volume of 27 cubic centimeters?

  54 square centimeters
• What is the volume of the largest cube with a surface area of 54 square centimeters?

  27 cubic centimeters
• What happens to the surface area to volume ratio as cubes increase in size?

  It decreases as size increases
• Why do larger organisms need transport systems?

  To transport molecules over longer distances
• What is the diffusion distance for a bacterium compared to a human?

  Bacterium is about one micrometer, human is 5 cm
• How much further do molecules have to diffuse in humans compared to bacteria?

  50,000 times further
• What are the specialized exchange surfaces in humans?

  • Lungs (alveoli for gas exchange)
  • Intestines (villi for nutrient absorption)
• What are the specialized transport systems in larger organisms?

  • Circulatory system
  • Blood vessels
• How do plants exchange substances and transport them?

  • Roots and leaves for exchange
  • Phloem and xylem for transport
• What does "large organisms" refer to in this context?

  Anything visible to the naked eye
• Who is the presenter of the video?

  Amadeus
• What does the learning platform offer?

  Videos, practice questions, and progress tracking
• Is the learning platform free?

  Yes, it's completely free
• Where can you find the link to the lesson?

  In the description below the video
• What is the purpose of the playlist mentioned?

  To organize all videos for the subject
• What is the final message from the presenter?

  Hope you enjoy and see you next time