Gymnosperms Flashcards
How many living species of gymnosperms are there?
1000
Do gymnosperms dominate any ecosystems?
Many ecosystems
What are the 4 phyla of gymnosperms?
Coniferophyta, cycadophyta, ginkgophyta, gnetophyta
How many species of conifers are there?
630
What trees are included in coniferophyta?
Pines, firs, spruce, larches, junipers
What type of leaves do conifers have? Why are these an adaptation?
Needles. They are resistant to drought and frost
What are the traits of pine needles?
Bunched together at the base in groups of 2-5, with a sheath at the bottom. Rigid and sharp
What are the traits of larch needles?
> 5 short, soft needles bunched together. Only deciduous conifers
What are the traits of spruce needles?
Individual needles. Are square-ish and you can roll them between your fingers
What are the traits of fir needles?
Individual needles that are flat
What structure seen in seedless vascular plants has been modified into a cone in gymnosperms?
Strobili
Are conifers monoecious or dioecious?
Monoecious, but separate micro and megasporangiate cones
Are conifers wind or animal pollinated?
Wind pollinated, produce huge amounts of pollen
Where are the microsporangiate and megasporangiate cones located on a conifer?
Microsporangiate cones are located at the top of the tree to be able to catch the wind, while the ovulate cones are further down
How many species of cycads exist? Where are they found?
300 species that grow in tropical areas
Are cycads monoecious or dioecious?
Dioecious
Are cycads wind or animal pollinated?
They are insect pollinated and produce nectar to attract insects
What is unusual about cycad and ginkgo sperm?
Flagellated. Only cycads and gingkos have flagellated sperm, the conifers have lost that trait
What are the morphological traits of cycads?
Shrubby or tree-like with palm-like pinnate leaves, deeply incised margins. The leaves grow in a rosette, and have large cone-shaped strobili
How many species of ginkgos are there?
Only 1
Are ginkgos monoecious or dioecious?
Dioecious
What is the “fruit” of a ginkgo?
The seeds. Have a fleshy coating that smells like vomit
What do the leaves of ginkgos look like?
Fan shaped with veins radiating out into the leaf blade
How many species of gnetophytes are there?
75 species
What are the 3 living genera of gnetophytes?
Gnetum, Ephedra, Welwitschia
Why are gnetophytes weird?
Share some traits with gymnosperms and other traits with angiosperms. We put them with the gymnosperms mainly because we don’t know what to do with them
What traits are found in gnetophytes that are common with angiosperms?
Vessel elements, some have a variation of double fertilization, some produce nectar and are insect pollinated, some lack archegonia
What traits are found in gnetophytes that are common with gymnosperms?
Some produce nectar and are insect pollinated like cycads, all have cones and leaf morphology similar to gymnosperms
