lecture 10+11

Question 1

Name the apomorphies of the euphyllophytes, and list the two major, vascular plant groups included

Answer 1

cp DNA inversion
leaves euphyllous
root protoxylem exarch
vascular plant groups:
- monilophytes
- lignophytes (woody plants)

Question 2

Name the putative apomorphies of the monilophytes, and list the five major groups contained within it

Answer 2

siphonostele
stem protoxylem mesarch

equisetales
maratiales
polypodiales
ophioglossales
psilotales

Question 3

What is distinctive about the leaves of the ophioglossid ferns?

Answer 3

leaves have sterile and fertile segments

Question 4

What is a eusporangium?

Answer 4

a sporangium that arises from a group of epidermal cells

Question 5

What is a fossil member of Equisetales, making up a component of coal deposits.

Answer 5

Calamites

Question 6

Name the major apomorphies of the Equisetales.

Answer 6

spores w/ elaters
sporangiophore
leaves reduced, whorled
stems ribbed with canals

Question 7

What is the only extant genus of the Equisetales?

Answer 7

equisetum

Question 8

Describe the morphology of the strobilus (cone), sporangiophore, and sporangia of Equisetum

Answer 8

Sporangia are homosporous, born in terminal strobili (subtended by a whorl of sheathing leaves), consisting of an axis bearing numerous, peltate sporangiophores, each (at maturity) bearing 5-10 sporangia beneath the distal, hexagonal outer portion; dehiscence is longitudinal (parallel to the axis of the elongate sporangium)

Question 9

What is unique about the spores of Equisetum? What is the function of this novelty?

Answer 9

The spores have four elaters, which are flexible ribbon-like appendages that are initially wrapped around the main spore body and that deploy upon drying or fold back in humid air

Question 10

Describe the diagnostic features and a putative apomorphy of the Marattiales.

Answer 10

• ~ six genera
• Large pinnate or
  bipinnate leaves
• Sporangia on the
  abaxial surface
• Photosynthetic
  gametophyte – fused
  in a synangium

Question 11

How do the gametophytes and leaf development of the Marattiales resemble the Polypodiales?

Question 12

What type of sporangium is found in the Marattiales?

Answer 12

eusporangiate

Question 13

What is the major evolutionary novelty of the Polypodiales? Describe its development and morphology.

Answer 13

• Primary apomorphy:
  Leptosporangium
• Develops from a
  single cell
• Single-celled
  sporangium wall
• Often aggregated
  into clusters: sori (sl.
  Sorus)

Question 14

Define sorus, indusium, annulus

Answer 14

• Sori hold spores
• indusium – protective flap of tissue over sori
• Annulus: * Important adaptation for
  spore dispersal

Question 15

In a fern gametophyte, what is the name of the male gametangium? the female gametangium? What do
they look like?

Answer 15

male- antheridia (sack of cells)
female- archegonia (flask-like structure)

Question 16

Name three or more genera of aquatic ferns.

Answer 16

Pilularia, Regnellidium,
and Marsilea
Azolla, with a symbiotic
N-fixing cyanobacteria in
leaf clefts – used in some
rice farms

Question 17

What reproductive features unite the aquatic ferns?

Answer 17

All the aquatic forms are
heterosporous and
endosporous

Question 18

What are the major evolutionary novelties for the lignophytes?

Answer 18

wood, seeds

Question 19

What are the products of secondary growth of the vascular cambium? the cork cambium?

Answer 19

• Vascular cambium:
  differentiates into phloem
  towards the periphery,
  into xylem (wood)
  towards the center
• Cork cambium: secretes
  corky cells; water-proof
  layer and physical
  defense (lenticels)

Question 20

Name four ways that seeds are adaptive

Answer 20

• Protection: seed coats
  prevents damage, desiccation,
  and sometimes predation
• Dispersal unit: in many plants,
  specially modified for
  dispersal
• Sticky seed coat for animal
  dispersal
• Seed coat as “wings” for wind
  dispersal
• Dormancy mechanisms:
  ensure germination under
  determined conditions
• Temperature
• Sunlight
• Moisture
• Sustenance: the nutritive
  tissue provides energy for the
  seedling – aids in
  establishment

Question 21

What were the basic features of Archeopteris?

Answer 21

• Devonian - Carboniferous
• Large wooden tree, but
  leaves like a fern
• Sporangia on fertile
  branches
• Some species were
  heterosporous

Question 22

What is a pteridosperm (seed fern )?