Table 2. Overview of growth kinematics.

Growth can be categorized as volume, area, and length growth. Depending on the biological system, a selection of growth types and corresponding growth tensors for growth factors ϑ₁, ϑ₂, and ϑ₃ and growth directions n₁, n₂, and n₃ is shown. Illustrations of how the growth would change unit volume, area, or length are portrayed. The right column summarizes common forms of growth kinetics, linear and exponential.

Growth Type	Growth Tensor	Growth Evolution
Volume	General Anisotropic Growth ϑ1 n1 ⊗ n1 + ϑ2 n2 ⊗ n2 + ϑ3 n3 ⊗ n3 Simple Isotropic Growth ϑI	Constant Growth Rate: $$\stackrel{.}{\vartheta }=G,$$ Growth: $$\vartheta (t)=1+G·t$$ Exponential Growth Rate: $$\stackrel{.}{\vartheta }=({\vartheta }^{\mathit{max}}-1)\frac{1}{\tau }\left(e^{\frac{-t}{\tau }}\right)$$ Growth: $$\vartheta =1+({\vartheta }^{\mathit{max}}-1)\left(1-e^{\frac{-t}{\tau }}\right)$$
Area	General Anisotropic Growth ϑ1 n1 ⊗ n1 + ϑ2 n2⊗ n2 Simple Isotropic Growth ϑI − ϑn3 ⊗ n3
Length	Single Direction Growth ϑ s ⊗ s