Kingdom Plantae includes the following five divisions:
(1) Thallophyta (Algae)
(2) Bryophyta
(3) Pteridophyta
(4) Gymnospermae
(5) Angiospermae
The first level of classification of plants is based on the presence and absence of well-differentiated distinct components in the body. Algae are separated from rest of the plants in having simple and less differentiated thalloid plant body. The next level of classification is based on the presence and absence of vascular tissues. This character separates the Bryophyta from the rest of the plants. Further classification is based on the ability to bear seeds. Pteridophytes do not bear seeds. Finally, the groups are formed on the basis, whether seeds are naked or enclosed within fruits. The gymnosperms have naked seeds, whereas angiosperms bear seeds enclosed within the fruits.
(i) Further classification is based on the ability to bear seeds and whether the seeds are enclosed within fruits or not.
(ii) Kingdom Plantae thus consists of Thallophyta, Bryophyta, Pteridophyta, Gymnosperms and Angiosperms.
Classification of Kingdom Plantae (Plants):