Plant phylogeny Flashcards
To look at the evolutionary pathway of major plant classes
What 3 major groups are plants divided into?
Grey plants (13 species), red plants (6000 species) and green plants (450,000 species)
In botany, what suffix is added to the name of a phylum?
-phyta
In botany, what suffix is added to the name of a class?
-phyceae/opsida
In botany, what suffix is added to the name of an order?
-ales
In botany, what suffix is added to the name of a family?
-aceae
In the phylogeny of green plants, what features denote a green plant?
Chlorophylls a/b
Starch inside chloroplasts
In the phylogeny of green plants, what features separate Streptophyta from various green algae species?
Asymmetrical, biflagellated male gametes
In the phylogeny of green plants, what features separate stoneworts and land plants from green algae?
Mitotic phragmoplast
Plasmodesmata
In the phylogeny of green plants, what features separate land plants from stoneworts?
Archegonium Antheridium Multicellular diploid sporophyte Multicellular sporangia Spores with sporopollenin
What are the 6 classes of land plant?
Liverworts Hornworts Mosses Lycopods Ferns Seed plants
In the phylogeny of land plants, what features are seen after the branching off of liverworts?
Stomata
In the phylogeny of land plants, what features are seen after the branching off of hornworts?
Water conducting tissue
In the phylogeny of land plants, what features are seen after the branching off of mosses?
Xylem and phloem
In the phylogeny of land plants, what features are seen after the branching off of lycopods?
Multi flagellate sperm
What is a monophyletic group?
Group contains all descendants of last common ancestor
What is a paraphyletic group?
Group contains common ancestor of all members but not all descendants of common ancestor
What is a polyphyletic group?
Group derived from more than one common evolutionary ancestor
What are monophyletic groups defined by?
Synapomorphies - shared, derived character states
What are paraphyletic groups defined by?
Shared ancestral character states
What are polyphyletic groups defined by?
Similar derived characteristics - the product of convergent evolution
What is a holophyletic group?
The same as monophyletic - group contains all descendants of common ancestor
What classes are included in the group Bryophytes?
Liverworts
Hornworts
Mosses
What type of group is the bryophytes?
Paraphyletic
In vascular plants, what is transported by the xylem?
Water and solutes
In vascular plants. what is transported by the phloem?
Photosynthates
What types of vascular organisation are seen in vascular plants?
Protostele
Siphonostele (with or without leaf gaps)
Eustele
What two branches do the seed plants divide into?
Gymonosperms
Angiosperms
What types of plant exist within the gymnosperms?
Cycads
Ginkgo
Gnetophytes
Conifers
What features separate angiosperms from gymnosperms?
Xylem vessels Carpel/fruit Flower Tectate microspore (pollen) wall Double fertilisation (embryo and endosperm)
Compare the xylem of conifers and angiosperm.
Conifers only have tracheids, which are less susceptible to freezing damage
Angiosperm have tracheids and vessel elements, which allows for rapid conduction of fluids and rapid growth
What are the main reproductive features of a flower?
Bisexual reproductive axis Stamen (male) - anther and filament Carpel (female) - stigma, style, ovary and ovule Ovary forms fruit Ovules protected within ovary
What general trends are seen in floral evolution?
Reduction and fusion Perianth - tepal -> clearly differentiated sepals and petals Petals - many, free -> few, fused Carpels - many, separate -> few, fused Ovary - superior -> inferior Spirals -> whorls
If carpels are free, the gynoecium is referred to as…
Apocarpous
If carpels are united, the gynoecium is referred to as…
Syncarpous
With a single carpel, the ovary is said to be…
Simple
With united carpels, the ovary is said to be…
Compound
What are the elements of the floral formulae?
Symmetry - radial or bilateral Tepals - number, free or fused Sepals - number, free or fused Petals - number, free or fused Stamens - number, free or fused Carpels, number, position, free or fused Fruit - type
What group is sister to the angiosperms?
Seed ferns (now extinct)
What are the major branches of the angiosperm phylogeny? (in order)
Amborella Water lillies Star anise Magnolias Monocots Eudicots
What is the scientific name of water lillies?
Nymphaeaceae
What is the floral formula for water lillies?
So, T5-n, An, Gs(n), berry
Give some features of water lillies.
Aquatic herbs
Pollinated by beetles
What are amborella?
Most primitive angiosperm
Xylem is only tracheid - like gymnosperm
What is the floral formula for Magnoliaceae?
So, T6-n, An, Gsn, follicles
What is the arrangement of perianth, stamens and carpels in magnoliaceae?
Stamens and carpels spirally arranged
Perianth appears to spiral but actually organised in groups of three
What are the features of monocots?
Monocolpate pollen
Single cotyledon
Usually parallel venation
Flower parts in 3s
What are the features of eudicots?
Tricolpate pollen
Two cotyledons
Usually reticulate venation
Flower parts in 4s or 5s