Topic 15: seedless vascular plants Flashcards

• during the first 100 million years of plant evolution, what dominated terrestrial vegetation

  bryophytes
• the earliest vascular plant fossils date to when

  ~425 mya
• early vascular plants had anatomical features intermediate between those of what to kinds of plants

  -bryophytes and vascular plants
• what were the anatomical features that early vascular plants had (3)

  -independent, branching sporophytes (not continuously dependent on gametophytes)-lacked leaves or roots-had no true vascular tissue (like byrophytes)
• what are the shared, derived traits of vascular plants (3)

  -life cycles with dominant sporophytes-vascular tissues-well-developed roots and leaves
• sporophyte dominant in what three things?

  -size-complexity-persistence
• in vascular plants, are the sporophytes continuously dependant on the gametophyte?

  no
• what do sporophytes have that gametophytes dont in vascular plants

  vascular tissue
• vascular tissue evolved only in what of vascular plants

  sporophytes
• vascular tissue allowed what to grow tall

  sporophytes
• what provided an evolutionary advantage over nonvascular plants

  vascular tissue allowing sporophytes to grow tall
• what are the two kinds of vascular tissue

  -xylem -phloem
• what is xylem

  vascular tissue that conducts water and minerals via dead, hollow cells that form continuous conduits throughout the plant
• what are water-conducting cells strengthened by

  lignin
• what is phloem

  vascular tissue that consists of living cells and distributes nutrients and organic products.
• what anchors vascular plants

  complex multicellular roots
• what are the 2 purposes of roots

  -anchors the plant-absorb and transport water and nutrients from the soil
• what is the purpose of leaves (2)

  -increase surface area-capture more solar energy for photosynthesis
• what are the two kinds of leaves

  -microphylls-megaphylls
• what are microphyll leaves

  small leaves with single vein
• microphyll leaves may have evolved as what

  -evolved as outgrowths of stems
• What are megaphyll leaves?

  Large leaves with highly branched vascular system
• What did megaphylls may have evolved as

  As webbings between flattened branches
• What are sporophylls


  Modified leaves with sporangia (spore-producing organ)
• What are sori

  Clusters of sporangia on the undersides of sporophylls
• Whats and example of sori

  Ferns
• What are strobili

  Cone-like structures formed from groups of sporophylls
• What are the traits of living vascular plants (3)

  -variation in spore sizes-sporophylls-two categories of leaves: microphylls & megaphylls
• What do vascular plants vary in among taxa

  Spore sizes
• most seedless vascular plants are what

  homosporous
• What does homosporous mean?

  producing one type of spore that develops into a bisexual gametophyte
• what is heterosporous

  taxa produce megaspores which give rise to female gametophytes and microspores, which give rise to ,ale gametophytes
• all seed plants and some seedless vascular plants are what

  heterosporous
• vascular tissue allowed seedless vascular plants to do what

  grow tall
• seedless vascular plants have what kind of sperm

  flagellated sperm
• how do the sperm in a seedless vascular plant reach the eggs

  must swim in a film of water to reach eggs
• what does fertilization in seedless vascular plants require

  water
• seedless vascular plants are most common in what kind of habitat

  relatively damp
• in contrast to bryophytes, sporophytes of seedless vascular plants are what

  are the larger and dominant generation
• what kind of gametophytes do seedless vascular plants have

  tiny independent plants that grow on or below the soil surface