Fig 5. Model results describing the evolving distributions of the nutrient concentration (a, c and e) and the proteoglycan volume fraction (b, d and f) within pellets for different initial aggregate radii, with κ = 0.005 and Σ₀ = 2, 3 and 4. (a-b) Σ₀ = 2; (c-d) Σ₀ = 3; (e-f) Σ₀ = 4.