Plant diversity & Evolution Flashcards
(24 cards)
How long have cyanobacteria and protists existed on land?
1.2 billion years
How long ago did plants colonize the world?
470 million years ago
When did forests first appear?
385 million years ago
When did plants evolve from green algae?
470 million years ago
What are the two alternate plant generations?
Gametophyte; Produces haploid gametes (egg & sperm) by mitosis.
They’re multicellular and found in primitive nonvascular plants.
Sporophyte; Produces unicellular haploid spores by meiosis.
They’re multicellular and diploid. Found in vascular plants.
What are embryophytes?
Plants are also known as embryophytes due to the significant derived trait of retaining and nourishing their embryos within parental tissues.
How did early plants get nutrients?
They had no true roots so depended on mycorrhizae.
Give some examples of nonvascular plants.
Bryophytes;
Liverworts
Hornworts
Mosses
Limitations of nonvascular plants.
Grow low to the ground.
Lack vascular tissue for long-distance transport of water + nutrients.
What are examples of seedless vascular plants?
Lycophytes; Club mosses, spike mosses.
Monilophytes; Ferns
What was the significance of seedless vascular plants?
Dead trees in Carboniferous swamps formed peat, which eventually became coal through heat and pressure.
What is the role of the ovule in seeded plants?
To produce the egg.
It has an opening for the pollen (sperm) to enter and fertilize.
What are the three main advantages of seeds?
Dormancy
Store food
Dispersal
What are the four phyla within gymnosperms?
Cycads
Ginko
Gnetophyta
Conifers
What are the two key adaptations of angiosperms?
Flowers; sepals, petals, stamen(pollen) and carpel (ovule).
Fruit; ovule is contained in the ovary and develops into fruit.
What percentage of plant species are angiosperms?
90%
How many described species of angiosperms are there?
325,000
What are the four main groups of angiosperms?
Basal angiosperms
Magnoliids
monocots
eudicots
Give examples of basal angiosperms.
Amborella
Water lily
Star anise
Give examples of Magnoliids.
Magnolias, avocados, cinnamon.
What are the largest groups of monocots?
Orchids, grasses and palms.
What families are included in the Eudicots?
The legume family and the rose family.
Monocot vs Eudicot characteristics. MONOCOT
One cotyledon
Parallel veins
Scattered vascular bundles.
Fibrous roots.
Pollen grain has one opening.
Flowers in multiples of three.
Monocot vs Eudicot characteristics. EUDICOT
Two cotyledons
Netlike veins
Vascular bundles in a ring
One main taproot
Pollen grain with three openings.
Flowers in multiples of 4/5
