Seed plants, Gamnosperms Flashcards
Seed plants have______ dominant and ___________ dependent
Seed plants have Sporophyte dominant and Gametophyte dependent.
What are the five innovations of seed plants?
- Independent sporophyte and dependent gametophyte
- Heterospory
- Ovules
- Pollen
- Seeds
What is a “Heterospory”
A seed plant produces two sizes of spores.
Megaspores and microspores
What are ovules?
- A megaspore retained within parent sporophyte.
What is pollen?
- A Microspore that develops into pollen grains
What is a seed?
Fertilized ovule develops into seed. Containing Next generation sporophyte.
True or false:
Within Seed Plants the Gametophyte is dependent on the sporophyte.
True.
How is a female Gametophyte developed?
Via Motosis from a megaspore.
When a Female gametophyte is being produced, where is the (1n) stage produced?
Within sporophyte megasporangium.
After the (2n) stage of a female Gametophyte is produced, what is it wrapped in?
integuments.
integuments + megasporangium + megaspore =
Ovule
What are the three componants of a Ovule?
Integuments
Megasporangium
megaspore.
is a Mircrospore 1n or 2n?
1n
Where is the microspore contained?
inside the 2n microsporeangium, which is retained on the parent sporophyte
How are Male Gametophytes produced?
Through mitosis of microspores
What is ‘immature pollen’?
tiny 1n male gametophytes.
how many cells are within a pollen grain at MINIMUM?
2 cells.
What are pollen grains coated in that makes them resilient?
Sporopellenin?
What happens when pollen reaches an ovule?
They ‘pollenate’ and then ‘fertilize’ the ovule.
How is pollen usually packed within a plant?
as single grains or small clumps of 4-16 grains.
How do orchids and milkweeds pack their pollen?
they clump them together in groups of 1000-1,000,000 grains.
What are the clumps of pollen created by orchids and milkweed called?
Pollinia
What aspect of pollen causes an allergenic response in people?
the proteins associated with the sporopollenin coat.
protective layer that makes them hardy and tough
in non-seed plants, it is the single-celled sperm that goes in search of eggs. Within seed plants, it is the _________ that goes must reach the egg.
Entire Male Gametophyte.
A Sporophyte embryo in gametophyte tissues in parent sporophyte wrapping is a……..?
Seed
What is the “dispersal stage” of seed plants?
The seed.
What is the “Dispersal stage” of non-seed plants?
a spore.
When did the first seed plants occur in the fossil record?
360 MYA
How many “main” clades of extant seed plants exist today?
Two
What are the clades of the seed plants found today?
Gymnoperms and Angiosperms
What does the root word “Gymnos” mean?
Naked
What does the root word “sperm” mean?
Seed
What does the root word “angio” mean?
Container, vessel.
When was the first Gymnosperm found?
305 MYA
When was the first angiosperm found?
125 MYA
gymnosperms and angiosperms probably arose from different __________________ ancestors.
progymnosperm
What characterizes a Gymnosperm?
seeds that is relatively ‘naked’
ie. ovule and seed lie on surface of sporophyll.
What is the normal shape for a gymnosperm sporophyll?
A stroblia (cone)
What are the 4 extant phyla of Gymnosperms?
- Ginkophyta
- Gentophyta
- Cycadophyta
- Coniferophyta.
Although the relationships between the 4 extant phyla of gymnosperm is not clear, they do appear to make up a __________ group.
Monophyletic.
How many extant species with the Phylum of Ginkophyta are there?
1 - Ginko biloba
Within Ginkophyta, what is a key characteristic of their sperm?
Flagellated sperm.
What are the madisonal uses of Ginkophyta leaves?
they are used increase blood flow (proven), and improve memory (not proven).
How many Extant specises of Cycadophyta exist?
roughly 130 species
Where are Cycadophyta found?
They are tropical areas, growing no taller than 1m high.
When were the Cycadophyta most dominant and diverse?
during the Mesozoic era.
What is a unique characteristic about Cycadophyta’s sperm?
Much like the Ginkophyta, the sperm is Flagellated.
What is the key way that Cycadophta seed are distributed.
Through birds/animals dropping them places.
How many Extnet species of Gnetophyta exist?
there are three Genera with about 76 extant spp.
What are the three main Genera?
Gnetum - 35 spp.
Weleitschia - 1 spp in Africa.
Ephedra - 40 spp
Some species of Epthedra contain alkioids called ________ and ________ that caused bronchi dilation.
Eqphedrine and pseudoephedrine.
How many specises of Coniferophyta exist?
This is the most species rich phylum with around 600 extant species.
What does the root word “fer” mean?
To bear.
What is special about Coniferophyta?
some of the species can live up to 3000 years old.
Most Coniferophyta are ________, and do not drop their leaves in autumn seasons.
Evergreen.
Some Coniferophyta are _______ and drop their leaves in the winter
deciduous.
what insects are responsible for the mass eradication of Coniferophyta across Canada?
Bark beetles.
What is a defense Conifers have that protect them from insects?
Pitch (resin)
