Plant biodiversity Flashcards
Plant Diversity
* Land plants (including the sea grasses) evolved
from a certain ________________ (charophyceans)
* >_______________ plant species on Earth today
* Most in ____________ environments (deserts,
grasslands, forests)
* Some have returned to ______________ habitats
(ex. sea grasses)
- green algae
- 390000
- terrestrial
- aquatic
Plants evolved
from ___________
(________ mya)
Evolution of
plants
* 4 main
evolutionary
events
- algae
- 500
4 main evolutionary events
top is the most recent
- radiation of flowering plants
- first seeds plants
- vascular tissues
- protected embryo
Eukaryotic Diversity: Plants
Characteristics of plants
* Eukaryotic, _________________,
photosynthetic
* Pigments: chlorophyll _______
* Cell walls: __________________
* Carbohydrate storage:
_________
* Developing _____________
protected by tissues of parent
plant
* Alternation of _______________
- multicellular
- a and b
3.cellulose - starch
5.embryos
6.generations
Plant Evolution
* Prerequisites for survival
– _______________energy
– CO2
– Water
– Inorganic nutrients
* Coping with life on the land
– ________________ and ___________ readily available
– But water?
* ___________________________
* Need ______________ and nutrients to support
metabolism and reproduction
- sunlight for energy
- sunlight and CO2
- dessication
- water
Eukaryotic Diversity: Plants
Challenges of a terrestrial environment
* Desiccation (_____________) – cuticle (_______ covering)
Stomata: for __________
and ________ diffusion
- drying out and waxy
- water and gas
Eukaryotic Diversity: Plants
Challenges of a terrestrial environment
* Protection of embryo from desiccation
Embryo within
___________ reproductive
structure
- female
Challenges of a terrestrial environment
* Water and nutrients - _________________(vascular tissue)
transport system
Eukaryotic Diversity: Plants Nonvascular, seedless plants
* ____________ terrestrial plants
(transitional plants)
* ______ true roots, stems, or
leaves (conductive tissue)
– Diffusion of nutrients and
water (cell to cell)
– Found in __________ areas
* __________,live close to
ground
– most <20cm in height
* Need ___________ for
reproduction
- Earliest
- Lack
- moist
- small
- water
Bryophytes
Three phyla of bryophytes
– _______ (Bryophyta)
– _________ (Hepatophyta)
– _________
(Antherocerophyta)
Note: Bryophyta refers only
to one phylum, but the
informal term “bryophyte”
refers to all
nonvascular plants
1.Mosses
2.Liverworts
3.hornworts
Bryophytes
_______________________ of lightweight spores
distributed bryophytes around the world
– Common in moist forests and wetlands
– Can inhabit _____________ environments
(mountaintops, tundra, and deserts)
- wind dispersal
- extreme
Mosses (Bryophyta)
* 15,000 species
* Arctic region to tropics
– Most in temperate
regions (______________
areas)
* Can store _____ quantities
of water and go dormant
during ____________
* Can ____________ of its
water but rehydrate and
reactivate cells when
moisture becomes
available
- damp shaded
- high
3.deiccation
4.lose all
Mosses (Bryophyta)
* Have “__________” shoot
* ______________ sporophyte
(long lived) consists of foot,
stalk, and sporangium
* Sporangium - site of
___________ and __________
production
* One sporangium can
generate over
__________________ spores
- leafy
- dependent
- meiosis and spore
- 50 million
Nonvascular Plants
* Sporophyte is ___________________________
– Cannot ____________ from maternal gametophyte
– Attached to parental gametophyte throughout
sporophyte lifetime
* Depends on ________________ for sugars, amino acids,
minerals and water
* Bryophytes have smallest and _____________
sporophytes of all modern ______________________
- photosynthetic
- live
- gametophyte
- simplest
- plant groups
Hornworts
(Anthocerophyta)
* ~_______ species
* Gametophyte is a ribbon-
like thallus
* Tall sporophyte (long
lived, remains __________,
______________________)
* Photosynthetic
___________________ grow
inside thallus, giving
hornwort a distinctive
blue-green color
- 100
- attached, photosynthetic
- Cyanobacteria
Liverworts (Hepatophyta)
Liverworts (10,000 species)
– Body flattened thallus or ____________ appearance
– Sporophyte ________ lived, _____________________
– Rhizoids (root-like structures)
* ___________plants, absorbs some nutrients/water
- leafy
- short lived, lacks chlorophyll
- anchors
Diplontic Life Cycle
(____________)
- Only _________
stage is
multicellular - Haploid cells
(gametes) are
unicellular
Meiosis
produces
___________
- animals
- diploid
- gametes
Alternation of generations
Non vascular plants
Gametophyte
* _______________(1n)
* Reproduce ______________
* Produce ____________ (1n)
(via mitosis)
* Either _________ or __________
* Antheridium (makes ________)
* Archegonia (makes ________)
* Most noticeable, dominant
phase of __________ life cycle
- haploid
- sexually
- gametes
- male or female
- sperm
- egg
- bryophyte
Alternation of generations
Non vascular plants
Sporophyte
* Diploid (2n)
* Reproduce ____________
* Produce ____________ (___n)
(via meiosis)
* Sporangium (makes spores)
* Attached to parent
gametophyte for ___________
___________________________
* _______, tucked inside female
- aseuxally
- spores (1n)
- water and nutrients
- small
Alternation of Generations
1. Gametophyte (haploid)
* Gametophytes produce
gametes
(______________________)
2. Fusion of egg and
sperm during fertilization
form a ___________ zygote
3. Sporophyte (___n)
4. Meiosis in sporophyte
* Produces ___n __________
5. Mitotic division of plant
spore produces new
_____________________
- egg and sperm
- diploid
- 2n
- meiosis
- gametophyte
Sporophyte
meiosis produces _________
Gametophyte
mitosis produces
_____________
spores
gametes
