The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved … See more

Land plants evolved from a group of freshwater green algae, perhaps as early as 850 mya, but algae-like plants might have evolved as early as 1 billion years ago. The closest living relatives of land plants are the charophytes, … See more

All multicellular plants have a life cycle comprising two generations or phases. The gametophyte phase has a single set of chromosomes (denoted 1n) and produces gametes (sperm and eggs). The sporophyte phase has … See more

There is no evidence that early land plants of the Silurian and early Devonian had roots, although fossil evidence of rhizoids occurs for several species, such as Horneophyton. The earliest land plants did not have va… See more

Leaves are the primary photosynthetic organs of a modern plant. The origin of leaves was almost certainly triggered by falling concentrations of atmospheric CO2 during the Devonian period, increasing the efficiency w… See more