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1
Kingdom Plantae
&
Kingdom Fungi
Chapter 18
�Multicellular
�Eukaryotic
�Photosynthetic autotrophs
�Most terrestrial
�Cells walls made of cellulose
�Contain a & b chlorophyll
Plantae Characteristics
�Plants evolved from a green algae, (Chlorophyta) ~ 500 million yr ago
�Commonalities include
� Chlorophyll a & b
� Store excess carbs as starch
� Cell walls of cellulose
�Differences include
� Algae lack true roots, leaves, stems, cuticles & support tissues
� Some algae are unicellular
� Algae lack vascular tissues
� Most algae aquatic; most plants terrestrial
Evolutionary History
2
Problems of Land Plants�Transporting water
� Developed vascular tissues (veins)
�Support
� Parenchyma cells – thin walls & usually remain
alive after they become mature. Parenchyma
forms the "filler" tissue in the soft parts of
plants.
� Collenchyma cells - thin primary walls with some
thickening of secondary wall. Provides extra
structural support.
� Sclerenchyma cells - thick lignified secondary
walls, often die when mature. Sclerenchyma
provides the main structural support to a plant
�Dehydration
� Cuticle helps prevent loss of water
� Stomata control loss of water
�Sexual reproduction
� Wind pollinated and insect pollinated
flowers increased chances of
reproduction
�Protection of embryo
� Ovary
� Seeds
Problems of Land Plants
4 Major Plant Groups
�4 main groups of land plants:
� Bryophytes – mosses
� Tracheophytes – have veins
� Lycophytes – club mosses
� Pteridophytes – ferns
� Gymnosperms – pines & conifers
� Angiosperms – flowering plants
3
Bryophyta Tracheophyte
↓ ↓Non-vascular Vascular
Lycophytes Pteriphytes Gymnosperms Angiosperm
Spores Spores Naked seeds Enclosed seeds
↓Monocot Dicot
↓ ↓
Non-flowering Flowering
� Embryo protection - all plants protect their embryos� Algae do not
� Mosses - lack vascular tissue but do protect their embryos
� Vascular tissue - Lycophytes� For water transport, have true roots, stems, and
leaves
� Megaphylls - Ferns� Increases amount of photosynthesis and
carbohydrates produced
� Seeds - Gymnosperms� Contains embryo and stored organic nutrients
inside a protective coat
� Flowers - Angiosperms� Reproductive structure to attract pollinators and
give rise to fruits
5 Evolutionary Events
�All land plants show alternation of
generations where 2 plants each produce
the other.� does not occur in the algae
�Gametophyte� Haploid cells
� Produces gametes - (egg & sperm)
� Zygote undergoes mitosis to form
sporophyte
�Sporophyte� Diploid cells
� Produces haploid spores• Spore - reproductive cell that develops into new
organism w/out the need to fuse with another
reproductive cell
Alternation of generations
4
Alternation of generations life cycle
FERTILIZATION
sporangium (2n)zygote (2n)
Mitosis
sporophyte
(2n)
gametophyte
(n)
Mitosis
spore (n)
diploid (2n)
haploid (n)
gametes (n)
Mitosis
MEIOSIS
� The dominant generation
� Generation that is larger, lasts longer, and is most visible
� Nonvascular plants - gametophyte dominant
� Vascular plants - sporophyte dominant
•Gametophyte becomes smaller and dependent
� In the history of plants, only the sporophyte generation evolves vascular tissue.
Alternation of Generations
5
�Bryophytes - nonvascular
�Lack true roots, stems, & leaves
�Gametophyte generation is dominant
�Sporophytes are smaller & present only
part of the time
�Flagellated sperm must swim in water
�Only a few cm tall
�Represented by 3 phyla:� liverworts
� hornworts
� Mosses
� Not every plant named “moss” is a bryophyte
• Irish moss is an alga, Spanish moss is an angiosperm
Bryophytes
�Mosses grow in damp, shaded
locations
�Become dormant in dry seasons
�Bryophytes are anchored by rhizoids
- small root like structures. They do
not play a role in absorption
Bryophytes - mosses
�Sporophyte consist
of the following:
� Stalk or seta
� Capsule or
Sporangium – stores
spores
� Operculum – lid of
capsule
� Haploid spores are
released that then
form a gametophyte
Bryophytes - Mosses
6
�Bryophytes have evolved several adaptations for life on land , but are not very successful.
�The other major groups of land plants evolved vascular tissue & are called Vascular plants.
� Vascular tissues transport H2O & nutrients thru the plant.
� Bryophytes lack water-conducting tubes & are referred to as “nonvascular plants.” Materials transported through diffusion
Diversity of Plants
Tracheophytes
�All plants with vascular tissues; EXCEPT Bryophytes
�Sporophyte is dominate generation
�Xylem – carries water &minerals upward
�Phloem – transports nutrients & stored food to roots & stems
�Have true roots to absorb water
�Have stems to transport materials
�Have leaves - photosynthesis
� All Tracheophytes are divided into 2 groups
� Seedless plants; spore produces
�Lycophytes and ferns
� Seed plants
�Gymnosperms and angiosperms
Tracheophytes
7
�Pteridophytes, seedless vascular
plants, (2 phyla)
� phylum Lycophyta - lycophytes
� phylum Pterophyta - ferns, whisk
ferns, & horsetails
Pteridophytes
�Most have true roots.
Pteridophytes
�Lycophytes have small leaves
with a single unbranched vein.
� These leaves, called microphylls,
probably evolved from tissue flaps on
the surface of stems.
�Leaves of other vascular plants,
megaphylls, are larger & have
veins
sporangia
sporophyll
Strobilus
stoma
strobili
leaves
(microphylls)
branches
arial stem
rhizome
root
Root
phloem
vascular tissue
Leaf
xylem
�Lycophytes -
club mosses� Among first
land plants to
have
vascular
tissue
� Small leaves
called
microphylls
with single
vein
Lycophytes
8
� Ferns
� Have megaphylls or fronds
•Large leaves with branched veins
•Immature leaves called fiddlehead
� Larger surface area for photosynthesis
� Better able to make food, grow, and
reproduce
� Sporangia located in sori on the
underside of fronds
� Small independent gametophyte
� Flagellated sperm; must have moist
environment
Pteridophytes
Pteridophytes
�Horsetails –
� Often found in marshy habitats
� Roots develop from horizontal rhizomes that extend along the ground.
� Reproductive stems produce cones at their tips.
� Cones consist of clusters of sporophyllsthat produce sporangia w/haploid spores.
Pteridophytes
9
�The phyla Lycophyta & Pterophyta
formed forest that later became
fossil fuels in the form of coal.
� Known as “Coal Age Plants”
Pteridophytes
�2 branches of seed plants-
Gymnosperms & Angiosperms
� Gymnosperm – naked seeds
� Angiosperm – enclosed seeds
�NO WATER NEEDED FOR FERTILIZATION
2 groups of seed plants
�Gymnosperms appears in the fossil record before angiosperms
�The ovules & seeds of gymnosperms (naked seeds) develop on the surfaces of specialized leaves called sporophylls.
� ovules & seeds of angiosperms develop in ovaries
Gymnosperms
10
�Phylum Coniferophyta - the largest
gymnosperm group, include pines,
firs, spruces, larches, junipers,
cedars, cypresses, & redwoods, yews
�Amongst the largest & oldest
organisms of Earth.
� Redwoods from northern California can
grow to heights of over 100 m
� 1 bristlecone pine from California is
more than 4,600 years old.
Gymnosperms
�Most are evergreen, retain their
leaves & photosynthesize
throughout the year.
� Some conifers, (redwood & cypress)
are deciduous
�Resin protects leaf from fungi &
insect attack
�Needle-shaped leaves are adapted
for dry conditions.
� A thick cuticle & the placement of
stomata in pits helps reduce water loss
Gymnosperms
�Angiosperms, flowering plants, are
vascular seed plants that produce
flowers & fruits.
�The most diverse, geographically
widespread & most successful of all
plants.
�All angiosperms are placed in the
phylum Anthophyta.
Angiosperms
11
�Angiosperms are ÷ into 2 classes,
monocots & dicots.
� Monocots have leaves with parallel
veins, dicots have netlike venation.
� Monocots have fibrous root systems,
dicots have tap roots
� Monocots have 1 cotyledon, dicots 2
� Monocots include lilies, orchids, corn,
yuccas, grasses, and grains.
� Dicots include fruit trees, vegetables
Angiosperms
� Monocots usually herbaceous
� Dicots usually woody
� Monocot flower petals in sets of 3
� Dicot flower petals in sets of 4 or 5
Angiosperms
12
�The flower is specialized for
reproduction
�The flower contributed to the
success of angiosperms.
The Flower
�Receptacle –base of flower w/stem
�Sepal (calyx) -modified leaves at
the base of the flower; enclose
flower before it opens
�Petals (corolla) -lie inside the ring
of sepals.
� Bright colors attract pollinators.
� Wind-pollinated plant typically lack
bright colors.
�Neither the sepals or petals are
involved in reproduction
The Flower
� Stamen - male reproductive organs
� A stamen consists of a filament (stalk) & the
anther where pollen is produced.
�Carpels (pistils) are female reproductive
organs.
� At the tip of the carpel is a sticky stigma that
receives pollen.
� A style leads to the ovary at the base of the
carpal.
� The swollen base is the ovary that will develop
into the fruit
� Ovules (seeds) are protected within the ovary.
The Flower
13
�Fruit is the mature ovary� As seeds develop from ovules after
fertilization, the wall of the ovary thickens
to form the fruit.
� Fruits protect dormant seeds
� In some plants the fruit functions like a kite or propeller, enhancing wind dispersal (maple)
� Many angiosperms use animals to carry seeds
• Burrs cling to animal fur.
• Edible fruits are eaten by animals & are deposited unharmed, along w/fertilizer.
Fruits
�The seed consists of the embryo, endosperm, & a seed coat
�As the ovules develop into seeds, the ovary develops into a fruit.
�After dispersal by wind or animals, a seed germinates if environmental conditions are favorable.
� During germination, the seed coat ruptures & the embryo emerges as a seedling.
� It uses the food stored in the cotyledons to support development.
Seeds
14
Seed Structures
� Seed coat – protection
� Cotyledon – stored food
� Hilum – scar where bean
was attached to pod (belly
button)
� Micropyle – small pore
where water enters
� Embryo – baby plant
� Radicle – root
� Hypocotyl – stem
� Epicotyl – 1st leaves
�Agriculture, the cultivation &
harvest of plants, began about
10,000 yrs. ago
�Agriculture made possible the
transition from hunter-gather
societies to permanent
settlements.
�The seeds of gymnosperms &
angiosperms enhanced the ability
of plants to survive & reproduce.
Success of Plants
�We depend on plants for food
production & oxygen.
�Flowering plants provide nearly all our food.
� Fruit, vegetables, corn, rice, & wheat are angiosperms.
�We also grow angiosperms for fiber,
medications, perfumes,
Human dependence
15
The Fungi
� Mycology – study of fungi
� Not plants—no chloroplasts; can’t
photosynthesize
� Not animals—heterotrophs
� Animals ingest their food, fungi absorb it
(chemoheterotrophs)
� Animals are motile, most fungi are not
� Fungi have windblown spores
during both sexual & asexual life
cycles
� Hyphae - thin filaments of cells
making up a fungus
� Mycelium - is mass of hyphae
making up main body of fungus
� The mushroom or puffball one
sees are not the main body of the
fungi, only temporary
reproductive structures
� The main body of a fungi is
Michigan is 38 acres beneath the
soil. (Humongous Fungus)
General Biology of a Fungus
16
� Fungi have thick cell walls.
� Do not contain cellulose like plants
� Contain chitin, like exoskeleton of
crabs and lobsters
� Septa or a wall divides the cells of
a hyphae in many fungi
� Hyphae give mycelium large
surface area for absorption of
nutrients
General Biology of a Fungus
� Black Bread Mold
� Stolen - horizontal hyphae on surface of bread
� Rhizoids – root like structures grow into the bread to anchor and carry out digestion
� Sporangiophore - stalk that bear sporangia
� Sporangium – spore case holding sporangia
� Sporangia - spores produced in asexual reproduction
� Sexual reproduction – 2 different mating typesmeet, tips of + and – hyphae join(conjugation), nuclei fuse, and a ZYGOSPORE results
� Zygospore germinates to produce sporangia
� Sporangia undergo meiosis to produce spores
� Spores give rise to new hyphae
Zygomycota
Life cycle of black bread mold
×50
NUCLEAR FUSION
zygote
thick-walledzygospore
haploid (n) wind-blownspores (n)
mating type
mating type
Asexualreproduction
mycellum
MEIOSIS
diploid (2n)
Sexualreproduction
Asexualreproduction
sporangium
–
+
17
� Mushrooms that one eats are fruiting body whose function is to produce spores
� The + and – hyphae join to form the mushroom fruiting body
� Mushroom has stalk and cap
� Basidia – club-like structures on the gills on
underside of cap
� Basidiaspores – sexual spores
Basidiomycota - Club Fungi
Ascomycota – Sac Fungi�Ascus – cup shaped fruiting body
�Ascospores – sexual spores produced in
ascus
�Conidiaspores – asexual spores produced
from hyphae
�Similar life cycle to Club Fungi
18
� Most fungi are saprotrophs
� Decompose remains of plants, animals, and microbes returning inorganic nutrients to soil
� Many are used to produce medicine
� Penicillium is used to produce the antibiotic penicillin
� Yeast is used in producing bread, beer, & other alcoholic drinks
� Soy sauce, cheeses and food itself
Ecological Benefits of fungi
� 2 different species live
together and help each
other out
� Lichens
•Fungus & cyanobacteria
or green algae
•Fungus acquires
nutrients & moisture
•Photosynthetic partner
makes food
Mutualistic relationships
Crustose lichen
Fruticose lichen
Foliose lichen
19
� Mycorrhizal fungi
� Mutualistic relationships with roots of plants
� Help plants grow more successfully in dry or poor soils
� Hyphae increase surface area for absorption of food and nutrients
� Fungus and plant exchange nutrients
Mutualistic relationships
� Mycoses – diseases caused by fungi
� Serious crop losses� 1/3 of world rice crop destroyed by rice
blast disease
� Potato blight in 1845 led to Irish
immigration to US
� Corn smut
� Animal diseases� Thrush or yeast infections – white patches on
tongue
� Ringworm – red irritated rings on skin
� Athlete’s foot - red irritated skin on feet
� Histoplasmosis – from bird or bat droppings;
causes flu like symptoms
Fungi and Diseases