III. Vascular plants  (pteridophyta)

EVOLUTION OF LEAVES

spore-bearing leaves called sporophylls

In terms of size and complexity, leaves can be classified as either microphylls or megaphylls

TLS Online TPP Program

#Id: 1976

#XL - T Zoology

Abundance- Its size—the total number of individuals in the population that exist with in a defined area.

TLS Online TPP Program

#Id: 1977

#XL - T Zoology

Population density is the number of individuals per unit area. D=N/S  

TLS Online TPP Program

#Id: 1978

#XL - T Zoology

Crude density-Total number of individual divided by total area.

TLS Online TPP Program

#Id: 1979

#XL - T Zoology

Ecological density- Total number of individual divided by total useable area.

TLS Online TPP Program

#Id: 1980

#XL - T Zoology

TLS Online TPP Program

#Id: 5349

#XL - T Zoology

R0<1, The population eventually declines to extinction 

R0=1, The population size remains constant

R0>1, The population increases