Lecture 14 Seed Plants & Gymnosperms Flashcards
1
Q
what are the 5 derived traits of seed plants?
A
- reduced gametophytes
- heterospory
- ovules
- pollen
- seeds
2
Q
what kind of gameto/sporophytes do seed plants have?
A
- sporophyted dominant; gametophyte is microscopic and DEPENDENT
3
Q
what spores do seed plants produce
A
- 2: megaspores and microspores
- microsporangia –> microspores –> male gametophyte
- megasporangia –> megaspores –> fem gametophyte
4
Q
how many integuments do: gymno/angiosperms have?
A
- gymno: 1
- angio: 2
5
Q
what does an ovule consist of?
A
- megasporangium (2n) + megaspore (1n) + one or more protective integuments
6
Q
what are pollen?
A
- grains coated with sporopollenin
- have a generative cell + tube cell
- eliminates need for a film of H2O
7
Q
what are seeds?
A
- embryo + food supply + seed coat
8
Q
what is pollination?
A
- the transfer of pollen to a part of a seed plant containing ovules
9
Q
what are the two clades of seed plants?
A
- gymno: th enaked seed including conifers
- angio: flowering plants
10
Q
what are gymnosperms?
A
- naked seeds - exposed on sporophylls that form cones/STROBILA
- monophyletic
11
Q
what are the four phyla in gymnosperms?
A
- ginkophyta
- gnetophyta
- cycadophyta
- coniferophyta
12
Q
what are ginkohpyta?
A
- one living species - ginko biloba
- separate male and female sporophyte trees
- wind pollinated but sperm is still flagellated – suggest intermediate evolutionary stage but still in pollen grain
13
Q
what are gnetophyta?
A
- 3 genera: gentum, ephedra, welwitschia
- species are morphologically diverse
- group based on molecular evidence
14
Q
what are cycadophyta?
A
- very diverse and dom in Mesozoic
- have large cones - separate male and female sporophyte
15
Q
what are coniferophyta?
A
- named for their CONES which are SPOROPHYLLS
- most are evergreens, some decidious
- leaf shape varies: scale-like, long needles, flat leaves
