Transcript Kingdom Plantae

Kingdom Plantae
Botany - the study of plants.
Summary
All Plants are autotrophs that produce food by
photosynthesis.
 cell walls composed of cellulose.
 non-motile
 eukaryotic
 multicellular.
 Plants are loosely organized into 4 groups
based on the presence or absence of vascular
tissue and seeds.
Vascular tissue
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Vascular tissue - tissue that transports water
and sugars throughout an entire plant.
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Plants lacking vascular tissue are called
bryophytes.
Plants which have vascular tissue are called
tracheophytes.
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Vascular tissue is made up of xylem and
phloem cells.
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Xylem carries water and minerals to the leaves.
Phloem transports food synthesized in leaves
throughout the plant.
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Land plants have a
cuticle and stomata
(singular stoma).
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Cuticle is a noncellular
layer secreted by
epidermal cells to protect
cells from drying out.
Stomata are pores in the
epidermis of a plant, to
permit the exchange of
gases between the plant
and the air around it.
Life Cycles of Plants
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An alternating cycle of both a haploid gamete
stage (Gametophyte) and a diploid spore stage
(Sporophyte). This cycle is known as the
Alternation of Generations
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Sporophytes produce haploid spores through
meiosis (division of the chromosome) that can
grow without any fertilization.
The spore grows into a gametophyte that produce
male and female gametes that can fuse and develop
into another sporophyte
Alternation of Generations
Bryophytes
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Non-vascular plants:
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Mosses, liverworts, and hornworts
BRYOPHYTES
(Phylum Bryophyta)
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Nonvascular land plants use diffusion and osmosis to
transport materials throughout the plant.
small in size they grow close to the ground in moist,
shaded areas.
lack true roots, stems and leaves, they are anchored to
the ground by structures called rhizoids.
Bryophytes are the only plants to have a life cycle that is
predominantly in the haploid gametophyte stage. They
produce male and female gametes that require water to
allow the sperm to swim to an egg creating a zygote that
will develop into a new sporophyte.
Tracheophytes
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Vascular plants:
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Ferns, gymnosperms, and angiosperms
Sporophyte dominated life cycle
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Seedless (spore bearing)
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Seeded Plants
TRACHEOPHYTES
(Phylum Tracheophyta)
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Tracheophytes have vascular tissues (xylem &
phloem). That allow plants to grow much
taller, by being able to draw water up through
their bodies.
Means of reproduction:
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spores: for club mosses, horsetails, and ferns.
seeds: for flowering plants (angiosperms) and
conifers (gymnosperms).
Seedless Vascular Plants (Ferns)
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Reproduce by spores, and have an alternation of
generations that is dominated by the sporophyte
life cycle. (opposite non-vascular)
Ferns are the most diverse seedless vascular
plant. (dinner to decorations)
Life Cycle see page 173

Write a list of ALL key words that come out of the life
cycle of the fern. Underline any terminology you have
encountered before and note where you have used the
word before.
Seed Producing Tracheophytes
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There are two main groupings for seed
producing plants:
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Gymnosperms (conifers and relatives)- cone
bearing plants that have seeds exposed on their
cones scales.
Angiosperms (flowering plants) – plants with
protected reproductive structures that have
adaptations to increase the likelihood of
reproduction.
What is a Seed?
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A seed is a multi-cellular structure containing
an embryo and a food source.
The embryo consists of a:
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An immature root
An immature shoot
One or two seed leaves
Seeds have hard protective structures and can
survive without water for years. They can also
be carried great distances by animals etc…
Gymnosperms
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Have all normal plant
characteristics
Have seeds on their
cone scales
Most are coniferous
trees (pines, spruce,
etc…)
Survival Strategies
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Reproduction with male pollen and pollen tubes
removes the need for moisture.
Protective bark prevents water loss
Shape helps prevent snow/ice damage, and
increases the area for photosynthesis to occur.
Needle-like leaves have thick cuticle and sunken
stomata to prevent water loss.
Do not loose their needles so photosynthesis can
begin earlier and they do not need extra nutrients
to grow new leaves.
Angiosperms (flowering plants)
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Plants that protect their seeds within the body
of a fruit.
Make up ¾’s of all plants, including:
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Trees, shrubs, herbs, grasses, water plants, etc…
Divided into two large classes based on the
number of seed leaves (cotyledons)
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Monocots – one seed leaf (grasses, lilies)
Dicots – two seed leaves (roses, peas, maple trees)
Diversity and success of the
Angiosperms :
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The angiosperms are the most diverse plant
group.
They can self-pollinate (clone) or crosspollinate with another plant.
Also, this diversity is due to a variety of other
factors, such as:
1) Presence of specialized structures
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Plants attract animal pollinators with colour and a
supply of food (often nectar) to carry pollen from
plant to plant
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Different flower colors, smells, and shapes attract
different pollinators.
Eg. Bees can’t see red, so they are often on blue or
yellow flowers.
Flies are attracted to flowers such as stink-cabbage.
Many insects see UV spectrum. (See Fig. 6.14, pg.
177)
2) Seeds are protected
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Flowers are sporophytes that do not produce
spores.
The pollen grains, and the eggs are all that remain
of the gametophyte generation.
The embryo is enclosed in hard tissue to form a
seed. The seed case enables the embryonic plant to
survive adverse weather conditions such as
drought, hot or arid periods and cold.
3) Function of the fruit in seed
dispersal
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Some seeds in fruits are easily dispersed by
wind and by water. Eg. Coconut
Some fruits are eaten and dispersed by
animals. The seed resist digestion and will pass
intact in an animal’s feces to germinate in a
new spot.
4) The presence of specialized tissues
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Some plants possess special tissues and
behaviours to help them survive heat, cold, and
droughts.
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Eg. small leaf hairs and sunken stomata help to
reduce water loss.
Now make like a tree and leave!!