Angiosperms Flashcards
What are the varieties of primrose morph resulting in self-inconpatibility?
Pin and thrum (only seed when 2 varieties crossed)
What are sexual polymorphisms?
the presence of several discrete heritable variants that co-exist within local populations, and which are subject to selection pressures arising from classical sexual selection
What is dioecy?
a characteristic of a species, meaning that it has distinct male and female individual organisms. Dioecious reproduction is biparental reproduction.
What is gynodioecy?
Gynodioecy is the evolutionary intermediate stage between hermaphroditism (exhibiting both female and male parts) and dioecy (having two distinct morphs: male and female).
What is agamospermy?
Agamospermy is the asexual production of seeds and embryos without fertilization or meiosis. = CLONAL
What is autogamy?
self-fertilization
What is panmixis?
random mating
What is apomixis?
apomixis is asexual reproduction without fertilization
What is Dichogamy?
temporal separation of sexual organs
What is Herkogamy?
Spacial separation of sexual organs
What is the heteromophic S-locus?
‘SUPERGENE’ controls SI and morphological characters
Genetic consequence of selfing?
Alunt of genetically determined variation will deecline over time
Advantage and disadvantage of agamospermy
\+ reproductive assurance \+ fixes well-adapted genotypes - narrow niche tolerance - evolutionary DEADEND -Mullers Ratchet ( cant escape bad mutations)
What is secondary thickening?
The formation of new tissue by the repeated lateral division of cells in the cambium of a woody plant, adding successive layers of new growth
What is apocarpy?
the female reproductive organs (carpels) of a flower are not joined to each other. It occurs, for example, in the buttercup
What is a dehiscent fruit?
characterized by splitting or bursting open.
What is entomophily?
pollen of plants, especially but not only of flowering plants, is distributed by insects
What is synapomorphy?
a characteristic present in an ancestral species and shared exclusively (in more or less modified form) by its evolutionary descendants.
What is paedomorphosis?
retaining juvenile features as an adult.
Benefit of paedomorphosis in angiosperms?
faster life cycles
3 key innovations of south african ice plant clade Aizoaceae
1- wide band tracheiods
2- cylindrical leaves
3- hygrochastic capsules (fruit only open and release seeds when moist)
What is synnovation?
combination of diff. innovations drives diversifications
Key confluence of Bromeliads (epiphytes)?
Synnovation of epiphytism (+associated tank habit) and entangled seeds, sticky seeds, sucking seeds.
What is a bitegmic ovule?
having two integuments
What is the difference between monosulcate and trisulcate pollen apertures?
When there is only one polar furrow, the pollen is called monosulcate . When three apertures are present, the pollen is named trisulcate
What is paleobacterial redux
revisiting the age of the angiosperms
What is angiosperms closest sister group?
Gnetales
What is the name of the paraphyletic grade at the base of angiosperms?
ANITA
What is a gentale?
extant gymnosperm which is functionally dioecious
Why was the discovery of the archaefructus important?
a late Jurassic angiosperm? small aquatic plant with seeds in a carpel- disputed angiosperms appearing in Cretaceous
Name 3 plant types contained within dicotyledons
daisies, buttercups, cacti, legumes, water lily
Name 3 flower types found within monocotyledons
grass, sedges, petaloid monocots; orchid, tulip, palm tree
What is a dicotyledon?
a flowering plant with an embryo that bears two cotyledons (seed leaves)
What is a monocotyledon?
flowering plant with an embryo that bears a single cotyledon (seed leaf)
