Practical #2 - Bryophytes and Ferns

Question 1

Division Bryophyta

Answer 1

• Nonvascular plant
• Commonal call, moses
• Found in moist, shaded environments
• Gametophyte stage is domninant (unlike all other plants)
• Possess multicellular gametangia
• Archegonia and antheridia produce gametes

Question 2

What are 2 differences between Gametophyte and Sporophyte?

Answer 2

• Gametophyte
  
  • Haploid
  • produces gametes
• Sporophyte
  
  • Diploid
  • Produces spores

Question 3

Describe multicelluar sporangia

Answer 3

• located on sporophytes
• produce many haploid spres via meisosis
• Sporangia release spores
  
  • Spores germinate into the gametophytes

Question 4

Describe gametangia

Answer 4

• located on gametophytes
• gametes are produced and stored inside these multicellular strucutres

Question 5

Moss Phyllidia and Caulidia - Division Bryophyta

Answer 5

• Possess 1-layer thick cell walls to allow for osmosis.
• Hyaline cells
  
  • ​dead cell chambers that help store water

Question 6

What is the structure of the moss gametophyte?

Answer 6

• Gametophyte body is anchored in place with root like rhizoids
  
  • ​not true roots, dont transport water
• Caulidia (stalk) and phyllidia (leaf) are not true either because they do not possess vascular tissues
• Gametophores can be monoecious or dioecious

Question 7

What division does Protonema belong to? Describe some characteristics of this moss.

Answer 7

• Division Bryophyta
• The spore produces a protonema
  
  • ​mass of green fialments, one cell layer thick. Referred to as the “first thread”
• Protonema gives rise to the bulbis that has meristems that grow into gametophores
  
  • Gametophores are the gamete producing structure on the gametophyte
  • ​Gametophoreshave a stalk -caulidiumand whorls of leaves -phyllidia
  • Gametangia are located at the top of gametophoes

Question 8

What is the difference between monoecious and dioecious?

Answer 8

• Monoecious
  
  • When both the antherida and archegonia occur on the same gametophyte
• Dioecious
  
  • The individual gametophyte possesses either archegonia or antheridia but not both

Question 9

Desribe the 3 structural parts of the Moss Antheridium

Answer 9

• Located on the top of the gametophore
• Paraphyses - hair like structures that are non reproductive filaments surround the antheridia.
• Antheridium - sperm is located here
• Gametophore
  
  • Caulidia and phyllidia

Question 10

Describe the differente structures of the moss Archegonium

Answer 10

• Cynlindrical and project upward form the base of the gametangium
• Venter - base of the archegonium where the egg is located
• paraphyses - surround the archegonia
• Sperm swims down neck of archegonium, fuses with the single egg –>diploid zygote. THe zygote undergoes mitosis to produce the sporophyte

Question 11

Describe the structure of a Moss Sporophyte

Answer 11

• Consists of a foot (base), a seta (stalk structure), and a sporangium (or capsule).
• Dependent upon the gametophyte
• The foot collects nutrients from the female gametophyte
• Operculum - lid like structure on the sporangium
• Peristome- terminal opening of the sporangium where spores are released from

Question 12

Describe the aspects of the Fern Gametophyte

Answer 12

• Also known as the prothallium
  
  • ​small heart shaped structure
  • 1 cell layer thick
• Possess rhizoids to anchor the prothallium to the soil.
• produces antheridia and archegonia
  
  • found underneath gametophyte
• Sperm must swim through water
• After fetilization the zygote becomes a sporophyte
• Green, photosynthesis, can live for a while

Question 13

Fern facts

Answer 13

• Division Pterophyta
• Primitive vascular plants - xylem and phloem
• Sporic life cycle
• Gametophyte referred to as Prothallium
• Gametophytes are restricted to moist habitats
• Most diverse division of seedless vascular plants
  
  • • 11,000 species
• Sporophyte has horizontal stems called rhizomes

Question 14

What are the different parts of a Fern?

Answer 14

• Rhizome - horizontal root
• Root - true roots. Consist of xylem and phloem
• Frond - the leaf of fern (also called sporophylls)
• Fiddlehead - young sporophyte.
• Sori - where the spores come from. Located on the fronds

Question 15

Describe the structure of the Fern Sporophyte

Answer 15

• Frond (leaf)
  
  • young leaf is rolled into a tight coil, called a fiddlehead
• Petiole - stalk like structure that connects the fronds to the rhizomes.
• Simple or compound leaf structure
  
  • compound = leaflets called pinnae
  • ​Pinnae attach to central axis called rachis
• Rhizome attaches the fronds (vertical) and true roots (underground)

Question 16

Describe the characteristics of the fern sori and sporangia

Answer 16

• Sporangia are clustered together and called sori (sorus) on ferns
  
  • Found on the underside of fronds (also called sporophylls)
• Some sori are covered bny a thin membranous outgrowth - indusium
• annulus - thick cell wall of a sori that aid in dispersal of the spores

Question 17

What gives rise to fern protonema?

Answer 17

• The spore mother cells go through meiois inside the sporganium producing haploid spores
• When these spores germinate they give rise to the fern protonema that will give rise to the gametophyte