● Phyllotaxy is the `color{Violet}"pattern of arrangement"` of leaves on the stem or branch.

● This is usually of three types – alternate, opposite and whorled.

● `color{Brown}"Alternate"` : In alternate type of phyllotaxy, a `color{Violet}"single leaf"` arises at each node in alternate manner, as in `color{Violet}"china rose"`, `color{Violet}"mustard"` and `color{Violet}"sun flower"` plants.

● `color{Brown}"Opposite"` : In opposite type, a `color{Violet}"pair of leaves"` arise at each node and lie opposite to each other as in `color{Violet}"Calotropis"` and `color{Violet}"guava plants"`.

● `color{Brown}"Whorled"` : If `color{Violet}"more than two leaves"` arise at a node and form a whorl, it is called whorled, as in `color{Violet}"Alstonia"`.

● Leaves are often `color{Violet }"modified"` to perform functions other than photosynthesis, exchange of gases and transpiration (through stomata).

● `color{Brown}"Tendrils"` : They are converted into tendrils for `color{Violet }"climbing"` as in `color{Violet }"peas"` .

● `color{Brown}"Spines"` : They are converted into spines for `color{Violet }"defence"` as in `color{Violet }"cacti"`.

● `color{Brown}"Fleshy Leaves"` : The fleshy leaves of `color{Violet }"onion and garlic"` store `color{Violet }"food"`.



● In some plants such as `color{Violet }"Australian acacia"` , the leaves are `color{Violet }"small and short-lived"`. The petioles in these plants `color{Violet }"expand"`, become `color{Violet }"green"` and `color{Violet }"synthesise"` food.



● `color{Brown}"Insectivorous plants"` : Leaves of certain insectivorous plants such as `color{Violet }"pitcher plant, venus-fly trap"` are also modified leaves.

● A flower is a `color{Violet }"modified shoot"` wherein the `color{Violet }"shoot apical meristem"` changes to `color{Violet }"floral meristem"`.

● Internodes do not elongate and the axis gets `color{Violet }"condensed"`.

● The apex produces different kinds of `color{Violet }"floral appendages"` laterally at `color{Violet }"successive nodes"` instead of leaves.

● When a shoot tip transforms into a flower, it is always `color{Violet }"solitary"`.

● The `color{Violet }"arrangement"` of flowers on the floral axis is termed as `color{Violet }"inflorescence"`.

● Depending on whether the apex gets converted into a `color{Violet }"flower or continues to grow"`, two major types of inflorescences are defined – `color{Violet }"racemose and cymose"`.

`star` `color{Brown}"Rasemose"` : In racemose type of inflorescences the main axis `color{Violet }"continues to grow"`, the flowers are borne laterally in an `color{Violet }"acropetal succession"`.

`star` `color{Brown}"Cymose"` : In cymose type of inflorescence the main axis `color{Violet }"terminates in a flower"`, hence is limited in growth. The flowers are borne in a `color{Violet }"basipetal order"`.