Summary

This chapter classified the plant kingdom into four major groups on the basis of spore- versus seed-formation, the presence or absence of vascular tissue, and how far the plant body is differentiated into root, stem and leaves.

Algae are mostly aquatic, thalloid plants, divided into Chlorophyceae (green, freshwater, chlorophyll a and b, starch-storing), Phaeophyceae (brown, marine, fucoxanthin-bearing, mannitol/laminarin-storing) and Rhodophyceae (red, marine and freshwater, phycoerythrin-bearing, Floridean-starch-storing).

Bryophyta, the 'amphibians of the plant kingdom', are simple land plants needing water for fertilisation, with a dominant gametophyte and a small, dependent sporophyte; the group divides into liverworts (flat thallus, e.g. Riccia) and mosses (protonema plus erect leafy stage, e.g. Funaria).

Pteridophyta were the first true vascular land plants, with a dominant, independent sporophyte bearing true roots, stems and leaves (microphylls or macrophylls), and a small, separate gametophyte; examples include Selaginella, Equisetum and true ferns such as Dryopteris and Pteris.

Gymnosperms are seed-bearing plants with naked (unenclosed) seeds, a dominant sporophyte showing secondary growth, dimorphic leaves, and heterosporous reproduction on microsporophylls and megasporophylls; Cycas and Pinus are the chapter's key examples. …