Chapter 26/35 - Plants Flashcards
How long was Earth without terrestrial life
3 billion years
Roughly how many living plant species are there
290,000 species
What do plants supply
Oxygen
What green algae are related to plants
Charophytes (Charophyceans)
What major group of Eukarya do Carophytes fall under
Archaeplastids
What group is most closely related to land plants
Charophytes
Are land plants descended from modern charophytes
No
Who do land plants share a common ancestor with
Modern carophytes
What protects exposed zygotes in charophytes from drying out
A durable polymer called sporopollenin
What does sporopollenin do for land plants
Encases their spores
What did the movement of charophyte ancestors onto land provide
Unfiltered sun
More plentiful CO2
Nutrient rich soil
Few herbivores or pathogens
What challenges did land present to charophyte ancestors
Scarcity of water
Lack of structural support
What is thought to have opened the way to the appearance of plants (traits, non specific)
The accumulation of traits that facilitated on land
What are systematists currently debating about the plant kigdom
The boundaries
What group do some biologists think should be included in the plant kingdom
Green algae
Five key traits in nearly all land plants that are absent in charophytes
Alternation of generations Walled spores to produce sporangia Multicellular gametangia Apical meristems Cuticles and mycorrhizae
What is it called when plants alternate between multicellular stages
Alternation of generations
Is the gametophyte haploid or diploid
Haploid
Fusion in gametes gives rise to what?
The diploid sporophyte.
What does the diploid sporophyte produce and through what means?
Haploid spores, through meiosis.
The diploid embryo is retained in the tissue of what?
The female gametophyte.
What do placental transfer cells do?
They transfer nutrients from parent to embryo.
What are embryophytes?
They are land plants.
why are they called embryophytes?
They are dependent on the embryo that develops from the zygote of the parent plant.
What are sporangia?
Organs that produce spores through the sporophyte.
What do diploid sporophytes undergo?
Meiosis to generate haploid spores.
What do spore walls contain?
Sporopollenin.
What does sporopollenin do?
Make spore walls resistant to harsh environments.
Where are gametes produced?
In organs called gametangia.
What are archegonia?
Female gametangia- they produce eggs.
Where is the site of fertilization in plants (all plants or specific types??) ?
Archegonia
What are antheridia?
Male gametangia, the site of sperm production
How do plants sustain continual growth?
In their apical meristems.
Identify in picture!
Cells from apical meristems differentiate into….
Various tissues.
What are the oldest fossilized spores and tissue that have been extracted?
475 million year old rocks!!!!!!
What gave rise to a vast diversity of modern plants?
The ancestral species of the fossilized spores and tissues
How are land plants informally grouped?
Into vascular plants (w/ vessels) and vascular plants (or bryophytes)
What phylum do bryophytes contain?
Hepatophyta, Bryophyta, Anthocerophyta (What are common names)
What phylum do seedless vascular pants contain?
Lycophyta, Pterophyta (common name)
Gymnosperms phylums:
Cycadophyta, Ginkgophyta, Gnetophyta, Coniferophyta (common)
Angiosperm phylums:
Angiosperms=Anthophytes,
Monocots, Eudicots (Common names)
Bryophytes are:
herbaceous (nonwoody) plants
Mosses are most closely related to….
Vascular plants
Non vascular plants: life dominated by….
Gametophyte (occasionally a sporophyte)
Where do mosses inhabit????
Diverse, sometimes extreme environments…. but most common in moist forests and wetlands like…… (THE BOG)
“Peat moss” scientific name
Sphagnum
Why is sphagnum important
global reservoir of organic carbon!!!!!!!!!!
Fossils of the forerunners of vascular plants date back about?
420 million years.
These early tiny vascular plants had what!?
Independent, branching sporophytes
Living vascular plants are characterized:
Life cycles with dominant sporophytes
Vascular tissues called xylem and phloem
Well-developed roots to anchor plants and absorb nutrients and leaves for photosynthesis
in contrast to bryophtes, sporophytes of seedless vascular plants are…
the larger generation
The gametophytes are tiny plants that grow…
on or below the soil surface.
