Download Life Cycles in Plants

Life Cycles in Plants
Chapters 29 and 30
Marchantia, liverwort
Dominant gametophyte, dependent sporophyte, thalloid dichotomously branched plant
body, antheridia in chambers on upper side of antheridiophore, archegonia on under side of
archegoniophore, Sporophyte has foot, seta and capsule
Moss Plant
Dominant gametophyte, dependent sporophyte, leafy plant body, rhizoids, antheridia in and
archegonia on top of separate antheridiophore and archegoniophore, Sporophyte has foot, seta
and capsule, spores first germinate into multicellular branched Protonema
Lycopodium, Club Moss
Dominant sporophyte
Reduced gametophyte
Microphylls, apical strobili (spikes)
Homosporous, biflagellate sperms
Phylum: Lycophyta
Selaginella, a spike moss: heterosporous, microphylls, biflagellate sperm
Reduced independent male and female gametophytes
Phylum: Lycophyta
Equisetum, horsetail
Nodes with leaf sheaths and
branches
Apical strobilus
Spores wrapped with elaters
Phylum: Monilophyta
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/F/Ferns.html
Fiddlehead
Ginkgo biloba
Living fossil
Only plant with dichotomous
leaf venation
Ginkgo nuts used in Chinese
festivals
Gymnosperm
Phylum: Ginkgophyta
http://www.theplantencyclopedia.org/wiki/Ginkgo
Cycas revoluta
Dominant Sporophyte
Reduced dependent gametophyte
Pollen cone and leaves
Gymnosperm
Phylum: Cycadophyta
Male Cycas Tree
Female Cycas Tree
Pinus long and dwarf
shoots
Dwarf shoot
Limited growth, bears
pinus needles
Long shoot
Unlimited growth bears
apical bud, no needles
T.S. Pinus Needle
Epidermis
Stoma
Guard cells
Hypodermis
Mesophyll
Resin Canal
Phloem
Xylem
Thick, sunken stomata, hypodermis, only main vein are xerophytic
adaptations of Pinus needle
Pinus
Dominant Sporophyte
Reduced dependent gametophyte
Heterosporous, pollen and ovulate
cones, pollination, seed
Phylum: Coniferophyta
http://mrstewartburnabysouth.blogspot.com/2011_03_01_archive.html
Carpel
Anther
Mature flower on
sporophyte plant
(2n)
Germinating
seed
Nucleus of
developing
endosperm
(3n)
Microsporangium
Microsporocytes (2n)
MEIOSIS
Microspore
(n)
Generative cell
Tube cell
Ovule with
megasporangium
Tube nucleus
(2n)
Male gametophyte
(in pollen grain)
(n)
Ovary
Pollen
MEIOSIS
grains
Stigma
Pollen tube
Megasporangium
Surviving
Sperm
(2n)
megaspore
Embryo (2n)
Integuments
(n)
Tube
Endosperm (3n)
nucleus
Seed
Micropyle
Seed coat (2n)
Antipodal cells
Polar nuclei
Style
Female
in central cell
gametophyte
(embryo sac)
Synergids
Egg (n)
Zygote (2n)
Egg
nucleus (n)
FERTILIZATION
The Life Cycle of an
angiosperm
Key
Discharged sperm nuclei (n)
Haploid (n)
Diploid (2n)
Monocots versus Eudicots
Embryos
Leaf venation
One
cotyledon
Veins usually
parallel
Stems
Roots
Pollen
Flowers
Monocot
Characteristics
Root system
Vascular tissue usually fibrous Pollen grain
with one
scattered
(no main root)
opening
Floral organs
usually in
multiples
of three
Eudicot
Characteristics
Vascular tissue
Two
Veins usually usually arranged
cotyledons
netlike
in ring
Taproot
Pollen grain
(main root)
with three
usually present
openings
Floral organs
usually in
multiples of
four or five
Dicots included all flowering plants with 2 cotyledons.
Basal Angiosperms include 3 early lineages separated early
from main angiosperms.
1. Amborella trichopoda 2. Water lilies and 3. Star anise
Magnoliids separated next and are more similar to monocots
and eudicots than basal angiosperms. Magnoliids include
Magnolias, laurels and black pepper plants.
Eudicots are a clade and include remaining very large number
of angiosperms.
Living
gymnosperms
.
Bennettitales
Amborella
Water lilies
Most recent common
ancestor of all living
angiosperms
Star anise and
relatives
Magnoliids
Monocots
Eudicots
300
250
200
150
100
Millions of years ago
(b) Angiosperm phylogeny
50
0