The aim of the lesson today is to: 1.
Surface Area to Volume Ratio
Length of edge of cube / cm Surface area of whole cube / cm 2 Volume of cube / cm 3 Ratio of surface area to volume (χ:1)
Length of edge of cube / cm Surface area of whole cube / cm 2 Volume of cube / cm 3 Ratio of surface area to volume (χ:1)
Length of edge of cube / cm Surface area of whole cube / cm 2 Volume of cube / cm 3 Ratio of surface area to volume (χ:1)
Length of edge of cube / cm Surface area of whole cube / cm 2 Volume of cube / cm 3 Ratio of surface area to volume
Features of Specialised Exchange Surfaces. Large SA:Vol – increase rate of exchange Very thin – diffusion distance is short Partially permeable – allows selected materials to cross unobstructed Movement of environmental medium (air/water) – maintains diffusion gradient Movement of internal medium (blood) – to maintain diffusion gradient
Fick’s Law Diffusion∞ surface area x diff. in conc. length of diffusion path