Gymnosperms Flashcards
1
Q
general info
A
- naked seed
- trees or shrubs
- clusters of sporophylls = strobilus (cone)
- spores and gametophytes remain within sporophyte
- produce seeds but no flowers
- four phyla
2
Q
four gymnosperm phyla
A
- phylum pinophyta
- phylum ginkogophyta
- phylum cycadophyta
- phylum gnetophyta
3
Q
phylum pinophyta
A
- conifers
4
Q
structure of conifers
A
leaves are needles
- epidermis: waxy, sunken stomata
- hypodermis
- mesophyll
- veins
- fascicles
- evergreen
- some have scales
5
Q
examples of conifers
A
- ponderosa pine
- blue spruce
- larch
- lodgepole pine
6
Q
conifer wood
A
- soft (only tracheids
- contains resin canals that produce pitch
7
Q
reproductive cycle conifers male
A
- sporophytes are heterosporous
- pollen cones ( male strobili)
- 1 2n microsporocyte undergoes meiosis
- produces 4 1n microspores which undergo mitosis
- forms 4 pollen grains (4 cells each)
8
Q
reproductive cycle conifers female
A
- seed cones (female strobili)
- 1 2n megasporocyte goes through delayed meiosis
- produces 4 1n megaspores, three of them die and one of them goes through slow mitosis
- produces 1 female gametophyte which is 2-6 eggs in archegonia
9
Q
fertilization conifers
A
- no double fertilization
- generative cell goes thru mitosis
- creates sterile cell and spermatogenous cell
- spermatogenous cell goes thru mitosis
- produces two sperm cells, one dies and the other fertilizes the egg
10
Q
conifer modifications
A
- can produce yew and juniper female cone
11
Q
human uses for conifers
A
- boats, instruments, bows, pulp
12
Q
phylum ginkgophyta
A
ginkgos
13
Q
general ginkgo info
A
- living fossil: ginkgo biloba
- leaves grow from spurs
- parallel, dichot branched veins
- “maiden hair”
- widely planted
china, korea: female
US , EU: Male
14
Q
phylum cycadophyta
A
- cycads, sago plants
15
Q
cycadophyta general indo
A
- look like palm or tree fern
- fossils from upper paleozoic
- slow growing,
- toxic cyanobacteria