seedless vascular plants - all very similar to ferns

• sporophylls clustered to form strobili (cone-like structure)
• all have microphyll
• Lycophyta - club mosses
  • micropyll-covered stems (has single vein)
  • includes resurrection ferns
• Pterophyta - includes ferns, whisk ferns, scouring rush

gymnosperms - most contain seeds within cones

• heterosporous - microspores produced in male cones, megaspores created in female cones
• has microscopic gametophytes, completely dependent on sporophyte generation
• Cycadophyta - Cycades
  • resembles palm trees
  • evergreen, has cones/strobili
  • flagellated sperm
• Ginkgophyta - only 1 species (Ginkgo tree)
  • dioecious, doesn’t have cones
  • fan-shaped leaves
  • female tree seeds have buyric acid (has stench)
• Coniferophyta - conifers
  • largest gymnosperm phylum
  • microsporophyll - male cone, located near bottom of tree
  • megasporophyll - female cone, located at top of tree, bigger than male cone
  • resin duct - used for protection, storage, wound-healing
  • stoma - gas exchange
  • epidermis - for gas exchange, protection, prevents desiccation
  • chlorenchyma - photosynthetic cells
  • endodermis - regulates transport in/out of vascular cylinder
• Gnetophyta - most similar to angiosperms