Monilophytes: Horsetails (Equisetopsida)

Question 1

Monilophytes

Answer 1

Clade of ferns + horsetails discovered using molecular sequence datasets

Question 2

Four clases of Monilophytes

Answer 2

1. Psilotopsida
2. Marattiopsida
3. Polypodiopsida
4. Equisetopsida

Question 3

Psilotopsida

Answer 3

whisk fern, moonworts

Question 4

Marattiopsida

Answer 4

marattioid ferns

Question 5

Polypodiopsida

Answer 5

remaining ferns

Question 6

Equisetopsida

Answer 6

horsetails and extint relatives

Question 7

Equisetopsida - Explain

Answer 7

Unusual among monilophites:

1. jointed stems
2. small leaves in whorls
3. whorled branches
4. cones

Question 8

Sporophyte

Answer 8

1. Rhizomatous
2. leaves and branches are in whorls
3. surface of stems has ribs
4. ribs alternate from node to node
5. Stomata between ribs

Question 9

Whorl

Answer 9

three or more leaves attached at the same level (node) on stem

Question 10

Node

Answer 10

region of the stem where a leaf or leaves are attached

Question 11

Internode

Answer 11

region between two nodes

Question 12

Silica in epidermis

Answer 12

stem has rough texture (“scouring rush”)

Question 13

Silica

Answer 13

may be involved in support of stem

Question 14

peltate

Answer 14

(shield-like) structures that bear sporangia

Question 15

Strobilus

Answer 15

born at the tips of stems.

comprised of sporangiophores and pelate

Question 16

sporangium / sporangia

Answer 16

produces spores that germinate into tiny gametophytes.

Question 17

Sporangiophores

Answer 17

Strobili of whorled peltate structures (sporangiophores) bearing
sporangia on underside

Question 18

Ribs on sporophyte stem

Answer 18

1. Alternate from node to node

2. stomata between ribs

Question 19

Equisetum

Answer 19

1. Homosporous.

2. Only living memeber of Equisetopsida

Question 20

Elaters on spores

Answer 20

Four elaters on spore wall (help in dispersal).

Sensative to moisture and uncoil as they drie.

Question 21

Gametophytes on Horsetails

Answer 21

1. unisexuial (male) or bisexual

2. Rhizoid-bearing and a “leafy” reagions

Question 22

homosporous

Answer 22

producing spores of one kind only

Question 23

Equisetum stem anatomy

Answer 23

1. Open canals are associated with the vascular bundles and also occur in the cortex
2. There is also a large, hollow pith cavity.
3. nodes are solid.

Question 24

Pith cavity

Answer 24

canal in the center of the stem