•          All plants are photosynthetic, multicellular, sexually reproducing, eukaryotic organisms.

•          Plants evolved from a multicellular green alga more than 430 million years ago according to fossils.

•          There are probably more than 500,000 different plant species.

•          Plants have special structures, such as leaves, stems and roots, which algae lack.

•          Water enables fertilization by providing sperm with a medium to swim.

•          Alternation of generations means that there are 2 phases in life cycle of plants.

•          The early plants needed water to supply nutrients, photosynthesis and fertilization.

•          The cuticle was an adaptation enabled plants to conserve water by slowing evaporation from plant body.

•          Early plants were probably short and had no roots, leaves, or stems.

A nonvascular plant must have liquid water to reproduce.

They have long, thin strands of cells called rhizoids instead of roots.

Over 90% of modern plants are vascular.

Vascular plants have roots for absorption of water and support.

Guard cells – special cells that control size of pore on leaves.

One adaptation of new plants was compound lignin that made cell walls harder.

Some plants have bud scales that protect them from cold.

Some plants produce compounds  that act like antifreeze.

Plants can cope with drought by losing their leaves and  become dormant.

Seeds in fruit that is eaten by animals are often left far from the parent plant.

Ferns are the most numerous seedless vascular plants.

Plant kingdom is divided into 10 divisions.

Bryophytes all reproduce without seeds.

They lack true leaves and roots.

Angiosperms – vascular plants that produce seeds enclosed and protected by a fruit.

Dicot – angiosperm whose embryo has two cotyledons.

Plant remove carbon dioxide from air and release oxygen during photosynthesis.

Food chain – series of organisms thru which energy moves, in the form of food.

90% of food comes directly or indirectly from just 20 different kinds of cultivated plants.