Chapter 30 Flashcards
(30 cards)
What is a seed?
A plant’s reproduction mechanism, can produce another plant.
What does a seed consist of?
Seed Coat
Plumule
Hypocotyl
Radicle
Cotyledon
What adaptations do seeds have over spores?
-They can be dormant for years until planting
-Resistant to water shortages
-Exposure to UV radiation
-Have a supply of stored food
-They can be transported long distances
-Require no water for fertilization
What is Heterospory?
The presence of spores of 2 different sizes and sexes. Microsporangia are Males and Megasporangia are females.
What is the Ovule?
The organ that forms seeds, consists of megasporangium, megaspore, and one or two protective integuments.
What are the 4 traits common to all seed plants?
- Reduced Gametophytes
- Heterospory
- Ovules
- Pollen
What is a pollen grain, and its main role in pollination?
A developed Microspore. Fertilizes the ovule.
How does pollen get dispersed?
By air or animals.
What features characterize a gymnosperm?
-Better suited to nonvascular plants
-Served as food for herbivorous dinosaurs
-Produce cones, but not flowers
Describe reproductive features of a gymnosperm.
The big cones are female and above them are the male cones that are much smaller. The pollen blows into the female megaspore.
What are the 4 gymnosperm phyla?
Cycadophyta (cycads)
Gingkophyta (one living species: Ginkgo biloba)
Gnetophyta (three genera: Gnetum, Ephedra, Welwitschia)
Coniferophyta (conifers, such as pine, fir, and redwood)
What are the 3 key features of gymnosperm?
- Miniaturization of their gametophytes
- Development of seeds from fertilized ovules
- The transfer of sperm to ovules by pollen
What are some details about the Cycadophyta Phylum?
-Individuals have large comes like palm trees
-Are endangered
-Live in tropics
-Cones are either male or females
-Pollinated by beetles
-Coating of photosynthetic bacteria on leaves (poisonous)
-Have flagellated sperm
-Live for over 1000 years
What are some details about the Ginkgophyta Phylum?
-One single species, Ginkgo Biloba
-Supplement for tinnitus and memory
-Have flagellated sperm
-Native to china
-Ornamental tree
-High tolerance to air pollution
-Very stable DNA
What are some details about the Gnetophyta Phylum?
-3 genera: Welwitschia, Gnetum, Ephedra, Welwitschia
-Several supplements
What are some details about the Coniferophyta Phylum?
-Largest of the phylums
-Very tall
-Photosynthesis year round
-Evergreen
-Greatly reduced leaves
What are the characteristics of an Angiosperm?
Fruits and flowers. Formed when the ovary wall thickens and matures.
When did Angiosperms first evolve and what evidence do we have of it?
305 million years ago, Bennettitales and Amborella are evidence
What are the 4 methods of seed dispersal?
- Wind
- Water
- Animals
- Explosions
What plants have what pollinators?
Bees – yellow and blue flowers
Hoverflies – white and yellow flowers
Butterflies – deep cone shaped flowers
Hummingbirds – red
Moths and Bats –White flowers
Why are global pollinators in decline?
Habitat destruction and Pesticides.
What are the differences between a eudicot and monocot?
Monocot: 1 cotyledon, parallel veins, scattered tissue, no main root, pollen with 1 opening, flowers in 2 or 3 (3,6,9)
Eudicot: 2 cotyledon, netlike veins, tissue in ring, taproot present, pollen grain 3 openings, flowers in 4 or 5 (4,5,10)
What are some details about angiosperm diversity?
-250,000 species
-2 groups are Monocots and Eudicots
What are the 3 basal angiosperms?
- Amborella
- Water lilies
- Star anise
