Chapter 3 Lesson 2PLANT GROUPS

What are the characteristics of Seedless, Nonvascular Plants?1. Mosses, Liverworts, & Hornworts• Have no vascular tissues to transport water and sugar• Remain small because they depend on osmosis & diffusion to

transport water and sugar• Have rhizoids instead of roots• Do not have true stems, leaves & roots• Importance: first plants to inhabit a new area create new soil

prevent soil erosion

What are the characteristics of Seedless Vascular Plants?

2. Ferns, Horsetails & Club Mosses• Ferns range in size from a few millimeters to 23 meters tall

and can live in almost any climate.• Clubmosses are not true mosses because they have vascular tissue and are about 25 cm tall. These were common millions of years ago.• Horsetails are usually less than 1.3 meters tall. There are 15 species alive today, but millions of years ago were a predominant plant species• Importance = our coal was formed from these plants that

lived 300 million years ago.• Have vascular tissues to transport water& sugar• Xylem – transports water & minerals from the roots to the leaves• Phloem – transports sugars from the leaves to the rest of the

plant• Have true roots, stems & leaves

What are the characteristics of Seed Plants?3. What’s so great about seeds?• Seeds have stored food• Seeds can germinate (begin to grow) without having to do photosynthesis right away• Seed plants do not need water for

the egg to be fertilized by the sperm. They produce pollen that delivers sperm cells to the egg. After fertilization a seed develops alone or inside a fruit.• Seeds have a young plant partially

developed inside them• Seeds are protected by a seed coat

Seed Plants without Flowers4. Gymnosperms• 4 groups : Ginkgoes

Cycads Gnetophytes

Conifers

Gymnosperms continued…Gymnosperm• Means ‘naked seed’ because the seed is not encased in a protective fruit• Conifer • means ‘carry cones’• This group is the most economically important• Largest and most diverse group• Called evergreens as they keep their needles year round• Include the oldest living trees on Earth

Seed Plants with Flowers & Fruits5. Angiosperms• The most abundant group of plants on Earth and are found in

every environment• Produce flowers• Attract pollinators which take pollen from flower to flower • Others are wind pollinated• Produce seeds enclosed in a fruit• Fruits help ensure the seeds survive as they are transported to

areas where new plants can grow• Fruits protect the seeds as they develop• Importance• Provide land animals with food• All of our food crops, many sources of wood, and fibers for clothing

(cotton) come from angiosperms