Specialised Exchange Surfaces

• What are specialized exchange surfaces?

  Parts of an organism for substance exchange
• What is the main aim of the video?

  To explain common features of exchange surfaces
• What are the main specialized exchange surfaces in humans?

  Alveoli and Villi
• What is the function of alveoli?

  To exchange oxygen and carbon dioxide
• Where are alveoli located?

  At the ends of the bronchioles
• What do Villi do?

  Help absorb nutrients like glucose
• What specialized exchange surfaces do plants have?

  Root hair cells and leaves
• What is the role of root hair cells?

  To absorb water and mineral ions
• How do leaves function as exchange surfaces?

  They absorb carbon dioxide from the air
• What are specialized exchange surfaces?

  Parts of an organism over which they exchange substances with their environment
• What are the main specialized exchange surfaces in humans?

  Alveoli in the lungs and villi in the small intestine
• What is the role of the alveoli in the lungs?

  To exchange oxygen and carbon dioxide between the air and the blood
• What is the role of the villi in the small intestine?

  To help absorb nutrients like glucose and amino acids
• What are the main specialized exchange surfaces in plants?

  Root hair cells and leaves
• What is the role of root hair cells in plants?

  To help absorb water and mineral ions from the soil
• What is the role of leaves in plants?

  To help absorb the carbon dioxide they need from the air
• What are the 5 main features of specialized exchange surfaces?

  Large surface area, thin, permeable, good blood supply, good external medium supply
• Why do specialized exchange surfaces need a large surface area?

  So more molecules can diffuse across at the same time, increasing the rate of diffusion
• Why do specialized exchange surfaces need to be very thin?

  So substances only have a short distance to diffuse across, allowing faster diffusion
• Why do specialized exchange surfaces need to be permeable?

  So the substances can diffuse across the surface rather than being blocked
• Why do specialized exchange surfaces need a good blood supply?

  To help maintain a concentration gradient for the substances being exchanged
• Why do specialized exchange surfaces need a good supply of the external medium?

  To help maintain a concentration gradient for the substances being exchanged
• What are the key differences between the function of alveoli in the lungs and villi in the small intestine?

  • Alveoli exchange oxygen and carbon dioxide, while villi absorb nutrients like glucose and amino acids
  • Alveoli are found in the lungs, while villi are found in the small intestine
  • Alveoli have a good supply of air, while villi have a good supply of food
• What are the key differences between the function of root hair cells and leaves in plants?

  • Root hair cells absorb water and mineral ions from the soil, while leaves absorb carbon dioxide from the air
  • Root hair cells are found in the roots, while leaves are found on the aerial parts of the plant
  • Root hair cells have a good supply of soil, while leaves have a good supply of air
• What is the formula to calculate the area of a circle?

  $A =$$\pi r^2$
• What are the key differences between scanning electron microscopes (SEMs) and transmission electron microscopes (TEMs)?

  • SEMs produce 3D images, while TEMs produce 2D images
  • SEMs are used for non-living samples, while TEMs can be used for living specimens
  • SEMs use a focused beam of electrons to scan the surface, while TEMs use a beam of electrons that passes through the specimen