According to the current hypothesis, the gradient in phototropin phosphorylation induces the movement of auxin to the shaded side of the coleoptile. Once the auxin reaches the shaded side of the tip, it is transported basipetally to the elongation zone, where it stimulates cell elongation. The acceleration of growth on the shaded side and the slowing of growth on the illuminated side (differential growth) give rise to the curvature toward light.

TLS Online TPP Program

#Id: 2193

#Unit 10. Ecological Principles

TLS Online TPP Program

#Id: 2194

#Unit 10. Ecological Principles

Facilitation may be important in early seral stages and inhibition important in later ones or vice versa. 

TLS Online TPP Program

#Id: 2195

#Unit 10. Ecological Principles

Morphological differences and the probability of invasion success

TLS Online TPP Program

#Id: 2196

#Unit 10. Ecological Principles

Plant species richness with field age

TLS Online TPP Program

#Id: 2197

#Unit 10. Ecological Principles

Characteristics of early and late seral stages

TLS Online TPP Program

#Id: 2198

#Unit 10. Ecological Principles

Character                         early stage         late stage 

Root to shoot ratio                    high             low

Number of seed                         many            few

Seed size                                     small            large

Biotic potential                           high             low

Productivity per biomass           high             low

NPP                                              high             low

P/R ratio                                        >1               =1

Nutrient cycling                       open             closed

Importance of detrivores          less              more

Stratification                               No               Yes 

Regeneration ability                 more              less

Resistance ability                        less              more