PTEROPSIDA (FERNS) TYPE II  MARSILEA (Water fern) Occurrence Marsilea is an aquatic or semi aquatic plant. It is common in the temperate regions. It groNA in fresh water ponds and ditches in Punjab. Marsilea quadrifolia and Munilea minuta are commonly found in Pakistan. General

Structure of Leaf

STRUCTURE OF LEAF Different groups of plants hake different variations in the internal structure or foliage leaves. Hie leaves show different evolutionary adaptations for different environmental conditions. The leaf tissues are divided into three fundamental systems. These are epidermal. mesophyll and vascular tissues. (a)


 SECONDARY GROWTH IN STEM The  stem increases in thickness In secondary growth. Secondary growth increases the  vascular tissues.  Therefore, it increases the thickness of flue stein. Secondary growth is common in gymnosperms and  woody dicots. But it is generally absent in most of the