Plant Introduction

• Charophytes were likely to have given rise to land plants during plant evolution
• Evidence of Charophytes giving rise to land plants:

  1.) Chloroplasts, cell walls, and sperm were very similar

  2.) Chlorophyll a and b are present in both charophytes and land plants

  3.) Molecular systematics
• Adaptations Land Plants made to survive:

  1.) Supporting mechanisms

  2.) Conducting tissues

  3.) Cuticles, pollen, and spores to prevent desiccation

  4.) Apical Meristem
• What are supporting mechanisms in plants?

  Vascular tissues and lignin
• What are conducting tissues in plants?

  Xylem and Phloem
• What are Apical Meristems?

  Growing points at the tips of roots and shoots, usually found in angiosperms
• Derived (unique to) Traits of Plant:

  1.) Apical Meristems

  2.) Alternation of Generation

  3.) Walled Spores in Sporangia

  4.) Multicellular Gametangia
• Derived traits of plants are:

  Found in almost all land plants but not in Charophytes
• Sporophyte generation is a:

  Diploid (2n) generation that goes through meiosis for spores
• Gametophyte Generation is a:

  Haploid (n) generation that goes through mitosis to produce the sperm and egg
• Meiosis is:


  A form of cell division that reduces the number of chromosome by half
• Mitosis is:


  A form of cell division that keeps the number of chromosomes the same
• When a plant produces one kind of spore it's called _____

  Homosporous
• When a plant produces two kinds of spores it's called _____

  Heterosporous
• Heterosporous spores include some seedless vascular and all vascular seeded plants
• Homosporous spores will be found in non vascular plants
• Megaspores are:


  Female spores
• Microspores are:


  Male spores