Plant Diversity

• Angiosperms (flowering plants) meaning “covered seed” (Greek angion = container)
• Gymnosperms

  meaning “naked seed” (Greek: gymnos = naked; sperm = seed)
• Five Key Traits of Seed Plants

  1.Reduced gametophytes – continuing the trend of sporophyte being dominant form 2.Heterospory – production of female megaspores and male microspores 3.Ovules - specialised structure for the megaspore 4.Pollen – specialised structure for the microspore 5.Seeds – specialised structure for the embryo
• One of the major distinctions between plants and the green algae is that  

  embryos are not retained within parental tissues in green algae
• The most recent common ancestor of all land plants was most similar to modern-day members of which group?  

  Charophycea
• Which of the following is characteristic of alternation of generations in land plants?  

  Meiosis in sporophytes produces haploid spores.  
• Bryophytes have all of the following characteristics except  

  lignified vascular tissue
• Plant spores give rise directly to  

  gametophytes.
• Each of the following is a general characteristic of bryophytes except  

  vascular tissue
• The following are all true about the life cycle of mosses except  

  gametes are directly produced by meiosis
• Beginning with the germination of a moss spore, what is the sequence of structures that develop after germination?

  1.  embryo

  2.  gametes

  3.  sporophyte

  4.  protonema

  5.  gametophore

  4, 5, 2, 1, 3  
• Bryophytes never formed forests (mats maybe, but not forests) because  


  they lack lignified vascular tissue.  
• The following characteristics all helped seedless plants become better-adapted to land except  

  a dominant gametophyte.  
• If a fern gametophyte is a hermaphrodite (that is, has both male and female gametangia on the same plant), then it  

  belongs to a species that is homosporous.  
• Plants with a dominant sporophyte are successful on land partly because  

  their gametophytes are protected by, and obtain nutrition from, the sporophytes.  
• Which of the following statements does not describe a portion of the pine life cycle?  

  Female gametophytes use meiosis to produce eggs
• The sori of ferns are both homologous and analogous to which structures?

  cones (strobili) of gymnosperm sporophytes  
• Assuming that they all belong to the same plant, arrange the following structures from largest to smallest (or from most inclusive to least inclusive).

  1.  spores

  2.  sporophylls

  3.  sporophytes

  4.  sporangia

  3, 2, 4, 1  
• Which of the following is true of seedless vascular plants?

  Whole forests were once dominated by large, seedless vascular plants
• Which of the following is not common to all phyla of vascular plants?  


  the development of seeds  
• A heterosporous plant is one that  

  produces microspores and megaspores, which give rise to male and female gametophytes.  
• The sporophytes of mosses depend on the gametophytes for water and nutrition.  In seed plants, the reverse is true.  From which seed plant sporophyte structure(s) do the immature (unfertilized) gametophytes directly gain water and nutrition?  

  sporangia
• Which of the following is not true concerning the sporophyte or gametophyte generations of flowering plants?

  The flower is composed of gametophyte tissue only.  
• Which of the following is an ongoing trend in the evolution of land plants?  

  reduction of the gametophyte phase of the life cycle  
• Plants with a dominant sporophyte are successful on land partly because

  their gametophytes are protected by, and obtain nutrition from, the sporophytes
• In terms of alternation of generations, the pollen grains of seed-producing plants are most similar to a  

  fern gametophyte that will bear only antheridia
• Gymnosperms differ from both extinct and extant ferns because they

  have pollen.