Question

What are the sub-group for plant Classification following the kingdom?

Answer 1

Hint: Kingdom plantae includes all plants. They are eukaryotic, multicellular and autotrophic. The plant cell contains a rigid cell wall. Photosynthesis occurs with the help of chlorophyll pigment, present in chloroplast.

Complete answer:
Classify as follows-
On the basis of body differentiation it is called thallophyta: body is not differentiated. Algae, bacteria and fungi fall in this Category. On the basis of differentiated body:
- Without specialised vascular tissue and
- With vascular tissue

Without specialised vascular tissue we have bryophyte. Bryophytes lack vascular tissue and are called as bryophytes. They are: liverworts, hornworts and mosses. They are found in moist areas but can survive in drier environments. It has about 20,000 species.

Based on vascular tissues presence: it is divided by seed producing or not producing. The one which lacks seed are –Pteridophytes. In this, the plant body is sporophytic.

The seed producing plants are called phanerogams. These are further divided on the basis of bearing naked seeds or having seed inside fruit. Seeds are naked in gymnosperms. These are used in food, timber medicine.

Seeds present inside fruit are present in angiosperms. The seeds are coated and developed in the organ or ovary. These are further divided by seeds having two cotyledons that are dicot plants and one cotyledon monocot plant respectively.

Note: RH Whittaker gave five kingdom classification for living organisms. Economic utilities of thallophytes. It is useful in the form of food stuffs, agriculture, in trade and business, in biological research, as the fodder of land. But there are many algae which act like pollutants and contaminate the drinking water. Also, watery equipment is rotten by the algae. Celphaleuros algae produce a disease called red rust in the tea plants.