Mosses and Ferns

1
Chapter 21

• Mosses and Ferns

2
Plants Invade the Land

• Land plants evolved from aquatic plants.
• At least two water-living algae groups evolved
  into land plants.
• One group evolved into the phylum Bryophyta and
  the other into phylum tracheophytes.

3
Plant adaptations for life on land

• There were several problems with life on land
  that were needed to be overcome for plants to
  live on land.
• All cells need a constant supply of water. This
  was no problem for those living in water, but
  those on dry land needed a way to solve this
  problem.

4

• Plants need sunlight to make food. The more area
  of the plant exposed to the sun, the better.
  Aquatic plants could float near the surface of
  the water, but land plants need to be vertical.
• Land plants needed to develop ways to move water,
  nutrients and other materials to all cells.

5

• Aquatic plants use water to help in reproduction.
  Land plants needed a different way to reproduce
  without the new plant drying out.