Download Bryophytes - Net Start Class

Plants
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• Roughly 80% of US money
contains traces of cocaine.
Did you know
• If you added up every blink in your lifetime
and used them all at once your eyes would
be closed for 1.2 years
What we already know…
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Multicellular
Eukaryotes
Autotrophs
Cell walls contain cellulose
Photosynthesis occurs in chloroplasts
using the pigment chlorophyll
Plant Life Cycle: Alternation of
Generations
• 2 alternating phases
1. diploid (2N) – called the
sporophyte, produces spores
2. haploid (N)- called the
gametophyte, produces
gametes
Alternation of Generations
What plants need to survive
1.
2.
3.
4.
Sunlight
Water and Minerals
Gas exchange
Movement of water and nutrients
Early Plants
Evolved from
green algae –
member of the
kingdom Protista,
a small plantlike
protist.
Early plants were
still restricted to
very wet areas
due to the lack of
true roots
5 Major Plant Groups in the Plantae Kingdom
NONVASCULAR
Mosses
(produce spores)
VASCULAR
Seedless
Seed
Ferns
(produce spores)
Gymnosperm Angiosperm
seeds in cones)
(
(seeds in
flowers
and fruit)
Monocot Dicot
Remember this chart!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
• VASCULAR TISSUES – specialized cells
that transport water and other
materials. Found almost all land plants.
Allows materials to be distributed more
efficiently.
• NONVASCULAR – relatively small plants
that have no vascular system.
How plants are grouped:
1. The presence or absence of
vascular tissue.
2. Their method of reproduction.
BRYOPHYTES:
Mosses, Hornworts and
Liverworts
Characteristics of Bryophytes
• Life cycle depends on water for
reproduction
• No vascular tissue, draw up water through
osmosis, lack roots – have RHIZOIDS:
long, thin cells that anchor
them into the ground.
• Low growing, small
• Found in moist, shaded areas
Important tems
• Archegonia – female sex structure,
where eggs are produced – much like the
ovary
• Antheridia – male sex structure that
produces sperm
• Sometimes both structures are found
on the same plant, others are on
separate plants.
Vascular Plants
Called Tracheophytes: ferns, gymnosperms
and angiosperms
• Evolution of vascular tissue, developed a
new cell that allowed them to conduct
water
• TRACHEIDS: hollow cells with thick cell
walls that withstand pressure. Allow water
to move more efficiently than osmosis.
Connected end to end like drinking straws
Vascular Tissues
• Allow plants to move substances against
gravity.
• XYLEM: transports water upward from the
roots to the rest of the plant
• PHLOEM: transports nutrients and
carbohydrates produced by
photosynthesis from the leaves
downwards to the rest of the plant
Seedless vascular plants
• Club mosses (P:lycophyta)–small plants
that live in moist woody areas, near
streams
Seedless vascular plants cont.
• Horsetails-(P:arthrophyta) commonly called
Equisetum or horsetails,
once used to scour pots
and pans in colonial times
because stems contain silica
Ferns: Phylum Pterophyta
• Seedless vascular plants
• Second largest phylum of the plant
kingdom
• Over 20,000 species
• Creeping underground stems called
rhizoids
Ferns
• Do not have seeds,
have spores, found
on the underside of
the leaf.
• Leaves are called
fronds.
• 1ST appeared 400
million years ago.
Clusters are called
sori (sorus) –
individual clusters are
called sporangia
1. What are the two types of vascular tissue?
2. What are the three phyla of seedless vascular
plants?
3. What is the dominant stage of the fern life
cycle?
4. What process is going on inside clusters of
sori?
5. How is water essential to the life cycle of
bryophytes?
6. What is the female reproductive structure
located in the gametophyte called? Male?
7. What characteristic of bryophytes is
responsible for their small size?
Seed Plants
• Divided into 2 groups, Gymnosperms and
Angiosperms
• Success is due to three things
1. water is not needed to reproduce
2. transfer of sperm is done by
pollination
3. embryos are protected in seeds.
Types of Vascular Plants: Seed = Gymnosperm
• Plants whose seeds
do not develop within
a sealed container
(fruit).
• Means “naked seed”
• Sperm is carried by
the wind.
• Ex. Pine trees,
cycads, conifers,
palm trees.
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GYMNOSPERMS
TVhe Svalbard Global Seed ault is seen Monday Feb.
25, 2008 in Longyearbyen, Norway. A 'doomsday' vault
built to withstand an earthquake or nuclear strike is
ready to open deep in the permafrost of an Arctic
mountain, where it will protect millions of agriculture
seeds from man-made and natural disasters. The
vault is to be officially inaugurated on Tuesday, less
than year after crews started drilling in Norway's
Svalbard archipelago, about 1,000 kilometers (620
miles) from the North Pole. The vault has the capacity
to store 4.5 million seed samples from around the
globe, shielding them from climate change, wars,
natural disasters and other threats.
(AP Photo/John McConnico)
• Place everything against
the wall except your
notes book and
something to write with.
FLOWERS:
Advantages of flowers
1. Allows plants to reproduce
without water.
2. Aid in attracting pollinators.
3. Aid in dispersal of seeds (fruit)
4. Holds reproductive structures.
FLOWERS
Flowers
Consist of 4 specialized leaves
 Petal – attracts insects and other
pollinators to the plant.
 Sepal – outermost leaf that
encloses the bud before it
opens, protects developing
seeds
Flowers: FEMALE Reproductive Structures
Called the 3. PISTIL or CARPEL. Contains
the ovary. Female gametophyte
PARTS OF THE PISTIL
1. Stigma – sticky top that grabs the
pollen
2. Style – the stalk of the ovary
3. Ovary – swollen lower portion where
ovules develop. Where fertilization occurs.
4. Ovules – eggs- become the seeds after
fertilization
Flowers: MALE Reproductive
Structures
4. STAMEN. Male
gametophyte
Parts of the stamen:
Anther – produces pollen, site of
meiosis
Filament – supports the anther
How Reproduction Occurs in
Flowers
1st – POLLINATION - pollen (male) is
transferred from the anther to the stigma.
2nd – Male pollen sprouts a pollen tube that
connects to the ovule and allows the
sperm to go directly to the egg.
3rd – FERTILIZATION- The sperm and egg
join
Fruit Formation
Following fertilization:
Ovary walls thicken to form a fruit to
enclose the developing seeds.
SEEDS
• Structure that contains the embryo of the plant.
• All seeds have four main characteristics:
1. Protection – seed coat keeps the seed from
drying out and protects from injury/disease.
2. Nourishment – nutrients are stored within
the seed.
3. Plant dispersal – spread by wind, water, or
animals. Prevents competition between the parent
and the offspring.
4. Delayed growth – most seeds will not sprout
until the conditions are favorable. Allows plants to
survive drought or cold winters.
PARTS OF A SEED
endosperm
Dicot seed
PARTS OF A SEED
1. Hypocotyl – connects cotyledon and radicle
2. Epicotyl - will become the shoot (contains
stems and leaves
3. Cotyledon – leaf-like structures
4. Seed coat – outermost layer, serves as
protection
5. Radicle – embryonic root
6. Embryo – developing offspring that the seed
protects.
7. Endosperm – provides nutrients to the
embryo
How seeds grow: Seed
Germination
• Germination occurs when the seed has
good growing conditions.
• Water enters the seed causing the tissues
to swell and the seed coat to break.
• If enough water is present it causes the
seed to grow.
• The first root and stem emerge.
Why Fruit?
Main goal is seed dispersal.
Animals eat the fruit and then
eliminate far away from the parent
plant.
This decreases competition of
the parent and offspring.
Fruits vs. Vegetables
• FRUITS HAVE SEEDS
• VEGETABLES DO NOT HAVE
SEEDS, THEY ARE EITHER
FLOWERS OR MODIFIED
ROOTS, STEMS OR LEAVES.
Roots, Stems and Leaves
• Plants are made up of 3 principal organs:
roots, stems and leaves
Plant Tissue Systems
• 3 types:
1. Dermal tissue – outer covering of
plant consists of a single layer of
epidermal cells. Usually covered by a thick
waxy coating called the cuticle
Trichomes – cells with tiny
projections making the leaf appear hairy
Guard cells- in epidermal layer on
underside of a leaf, regulate water loss
Vascular Tissue
• Moves water and nutrients through the
plant
• Several types of specialized cells
XYLEM – cells are called tracheids
(found in angiosperms and gymnosperms)
Vessel elements – found only in
angiosperms, wider than trachieds. Look
like stacked tin cans. Allows for continous
flow
Functions of ROOTS
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•
Anchor the plant
Hold soil in place and prevent erosion
Transport water and nutrients
Holds plants upright
3 Main organs of a Plant
1. ROOTS
2. STEMS
3. LEAVES
1. Roots: Major Functions
1. Anchor plant.
2. Absorb water and mineral
nutrients.
3. Function as storage in some
plants.
1. Roots: 2 Types
1. Taproot system– large
central root, with smaller
roots branching off. Serves
as storage .Ex. Carrots and
radishes
2. Fibrous root system – highly
branched root system.
How water and nutrients enter the root:
1. Osmosis – roots take in water
from the soil by osmosis.
2. Active transport – movement of
nutrients through the plant,
requires energy.
Roots
2. Stems: Major Functions
1. Support the leaves and house
the vascular tissue.
2. Serves as a highway that
transports materials to the
leaves and roots.
Adaptations of Stems
These functions include nutrient storage,
reproduction and protection. 6 Main types:
1. Runner – Airplane plant
2. Bulb – onion, daffodil
3. Corm - gladiolus
4. Rhizome – Ferns, strawberries
5. Tuber – potatoes, caladiums
6. Thorns
Adaptations of Stems
Stems
3. Leaves: Major Functions
1. Photosynthetic organ of the plant
– collects energy from the sun.
2. Manufactures food.
3. Leaves: Parts
1. Cuticle – waxy covering on the outside of the
leaf that decreases the rate of water
evaporation.
2. Epidermis – layer of cells found below the
cuticle that also prevent water loss.
3. Stomata- tiny holes in the epidermis that allow
for air exchange.
4. Guard cells – specialized cells that “guard”
the opening and closing of the stomata based
on the climate.
5. Mesophyll – cells found in the leaf – 2 distinct
layers.
6. Veins – made up of xylem and phloem,
vascular bundles.
3. Leaves: Mesophyll
1. Spongy mesophyll – inner layer of
loosely packed irregular shaped cells,
contain the vascular bundles.
2. Palisade mesophyll – where
photosynthesis actually occurs. Large
column shaped cells that contain many
chloroplasts.
Leaf structures
•
Adaptations of Leaves