Lecture 10

Question 1

aglaophyton

Answer 1

425 MYA, sporophytes not continuously nutritionally dependent on gametophyte, no vascular tissue, leaves, or roots

Question 2

6 characteristics of extant vascular plants

Answer 2

1. vascular tissue
2. complex multicellular roots
3. complex multicellular leaves
4. sporophyte dominant in life cycle
5. sporophylls
6. variation in spore sizes among species (heterosporous or homosporous)

Question 3

vascular tissue

Answer 3

allows taller growth and thicker bodies, xylem and phloem

Question 4

tracheids

Answer 4

dead hollow cells in xylem

Question 5

microphylls

Answer 5

leaves with a single vein of vascular tissue, usually small

Question 6

megaphylls

Answer 6

leaves with a branching vascular system, usually large

Question 7

sporophyte dominance in seedless vascular plants

Answer 7

dominant in size, complexity and persistence, not continuously nutritionally dependent on gametophyte

Question 8

sporophylls

Answer 8

modified leaves on sporophyte that bear sporangia

Question 9

cone aka strobilus

Answer 9

sporophylls arranged in overlapping scales

Question 10

homosporous

Answer 10

make one size of spore, gametophyte makes both eggs and sperm

Question 11

heterosporous

Answer 11

make two sizes of spores, small makes male gametophyte, large makes female gametophyte

Question 12

2 extant seedless vascular plant phyla (not monophyletic)

Answer 12

1. Lycophyta (1200)

2. Monilophyta (12 000)

Question 13

2 characteristics of seedless vascular plants

Answer 13

1. gametophytes are tiny independent plants on or just below soil surface
2. flagellated sperm must swim in a film of water to reach eggs

Question 14

phylum lycophyta

Answer 14

microphyllous, homo/heterosporous, existed as small herbaceous plants and giant woody trees in the Carboniferous, thrived in warm moist swamps, exist in cooler dryer climate, smaller survived

Question 15

lycophyta examples

Answer 15

quillworts, club mosses, spike mosses

Question 16

phylum monilophyta

Answer 16

almost all homosporous

Question 17

3 extant groups of monilophyta

Answer 17

1. whisk ferns
2. horsetails
3. true ferns

Question 18

whisk ferns

Answer 18

“living fossil” roots and leaves lost secondarily

Question 19

horsetails

Answer 19

brushy appearance, grow in marshy habitats, now single genus Equisetum

Question 20

true ferns

Answer 20

appeared in Devonian, most successful with 12 000 species, have megaphylls, produce sori on undersides of leaves, sporangia often have spring-like devices that catapult spores from the parent plant

Question 21

sori

Answer 21

clusters of sporangia

Question 22

scouring rushes

Answer 22

gritty silicon dioxide on horsetail stems used for cleaning cookware

Question 23

fiddleheads

Answer 23

edible young fern fronds

Question 24

flash powder

Answer 24

lycophyte spores used as flash powder by photographers, and for pyrotechnic displays

Question 25

Carboniferous (290-360 MYA)

Answer 25

lycophyta and monilophyta forests, continents flooded by shallow swamps

Question 26

coal swamps

Answer 26

dead plants in Carboniferous accumulated as peat, covered by marine sediments, heat and pressure converted to coal, decreased atmospheric CO2 and caused global cooling