Exam 3: Bryophytes Overview

Card Set Information

Exam 3: Bryophytes Overview
2014-04-12 10:31:33
Plant Kingdom
Show Answers:

  1. Bryophytes contribute significantly to what?
    the carbon cycle
  2. Similarities of bryophytes with green algae?
    • both have chloroplasts
    • asymmetrical motile cells with flagella that extend from the side and not the back
    • breakdown of nuclear envelope at mitosis
  3. Differences of green algae with bryophytes
    • 1) bryophytes have antheridia and archegonia with a protective layer of sterile cells
    • 2) retention of both the zygote and embryo in archegonium
    • 3) multicellular diploid sporophyte
    • 4) multicellular sporangia with spore-producing tissue
    • 5) meiospores with walls with sporopollenin
    • 6) tissues produced by apical meristem
  4. What do living bryophytes lack?
    water and food conducting vascular tissues called xylem and phloem
  5. Difference between bryophytes and vascular plants.
    bryophytes: gametophyte is the dominant stage

    vascular plants: sporophyte dominates
  6. What are thalli/
    undifferentiated bodies (not differentiated into roots, leaves, and stems)
  7. True or False:

    bryophytes show no sense of conduction at all.
    false; some thalli have a central strand of cells that are conducting
  8. What are ways that bryophytes can get food and water since they have no roots?
    • rhizoids anchor but special hairs aid in water transport and absorption by leaves and stems
    • bryophytes can have symbionts to aid in mineral absorption
  9. The __ is commonly stalked and consists of a __, one cell thick, that surrrounds numerous __, cells that develop into sperm cells
    • spherical or elongated antheridium 
    • sterile jacket layer
    • spermatogenous cells
  10. Explain the structure of bryophyte archegonia
    flask-shaped, with a long neck and a swollen basal portion (the venter), which encloses ONE egg

    outer layyer of neck and venter forms sterile protective layer of the archegonium

    central cells of the neck (neck canal cells( disintegrate when the egg is mature, resultinign in a fluid-filled tube, through wihich the sperm swim to the gg

    chemicals released that attract sperm
  11. Explain what happens with the archegonia after formation of the embryo.
    as teh embro develops, the venter's cells divide; and the enlarged venter is the calyptra
  12. Explain the bryophyte sporophyte.
    consists of a foot, which remains embedded in the archegonium, a seta, or stalk, and a capsule, or sporangium
  13. What is the advantage of matrotrophy (mother supplies all the nutrients)?
    they fuel the production of a many-celled diploid sporophyte, each cell of which is genetically equivalent ot hte fertilized egg, the cells of which can be used to produce many different haploid spores upon meiosis of the sporangium
  14. The sporophyte epidermis of mosses and many hornworts contains __-- each bordered by two guard cells--that are similar to those of vascular plants. 

    Explain the differences betwen the two.

    moss: open and close thus regulating gas exchange

    hornwort: once open, they remain open; can't close

    liverworts dont have any
  15. bryophyte spores germinate to form juvenile developmental stages, which in mosses are called __. From the __, __ and __ develop. These are characteristic of __ and some __, but not __
    protonema x2

    • gametophytes 
    • gametangia

    • mosses and liverworts
    • hornworts
  16. Explain the annulus
    special layer of unevenly thick-walled cells called an annulus

    as the sporangium dries out, contraction of the annulus causes tearing in the middle of the capsule

    the sudden explosion and snapping back of the annulus to its original position then results in a catapult-like discharge of the spores
  17. What are the parts of the fern sporophyte?
    the leaves (fronds), which acn be divided into pinnae, whichh are attached to rachis, an extension of the leaf stalk (petiole)

    young leaves are coiled adn called fiddleheads

    sori on the backside