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Week 7: Revolutions in biological diversity: plants and the transition to land.

Assigned reading: Chapter 30 in text
Quiz this week? Yes

Study Links:

• Fossil record
• Rhynie Chert
• See some information on Algal diversity (the ancestors!)
• Plants in Motion

Plant Evolution: from algae to redwoods

What do plants have in common?
What innovations occurred during plant evolution?

All Plants:

• are photosynthtic (autotrophs)
• are multicellular
• are eukaryotes
• contain chlorophyll a and b
• have embryos protected by parental tissue
• store carbohydrates as starch

What trends occurred during the evolution of plants?

Physiological problem of growing on land ...................Adaptations to that problem

Avoiding dessication but still getting CO2 ........................Evolution of cuticle and stomata

Transport of water through plants.....................................Vascular tissue, tracheids and vessels

The need to competing for sunlight................................... Turgor pressure in cells, deposits of cellulose and lignin in tracheids to become tall (erect)

Reproduction in absence of H2O.......................................Pollen for transport of male gametes, seeds for protection/dispersal of embryos