Transcript Chapter 8: Plants

Ice Breaker
• What are the characteristics of algae?
• Prokaryote or Eukaryote?
• Autotroph or Heterotroph?
• Outside covered by a Cell Membrane
or Cell Wall?
• What do you know about plants?
Chapter 8: Plants
Mrs. Charney
Northville Central School
Flowers of the Day
Foxglove
Gerber Daisies
Section One: The Plant Kingdom
• Plant- autotrophic,
eukaryotes, has many cells,
undergo sexual reproduction,
and surrounded by cell walls
• What makes them different
from algae?
• They are adapted to live
on land
• Have ways to obtain
and keep water
• Can transport
materials through their
body
Adaptations for Living On Land
• Retaining Water- plants
have a thick cuticle which
is a waxy coating that helps
to keep water in the plant
• Transporting Materialsplants have a system in
which water, minerals, and
food move throughout the
body
• Xylem- water goes up
• Phloem- food goes
down
Phloem
Xylem
Adaptations for Living on Land
• Support- low-lying plants do
not necessarily have this
problem, but large plants and
trees need to have rigid cell
structures and vascular tissue
(bark)
• Reproduction- plants undergo
sexual reproduction that can
be fertilized within a dry
environment
• Zygote- a fertilized cell
(sperm and egg are
together)
Classifying Plants
• Non-Vascular Plantsplants that lack a good
system for transporting
materials up and down
their bodies
• Low-growing plants
• Very slow method
• Vascular Plants- plants
that have true vascular
tissue (xylem and
phloem)
• Plants are taller
• Quicker method
Do you think
these trees would
need vascular
tissue?
Partnered Ice Breaker
• What are two characteristics of plants
that make them similar to algae?
• What is the difference between xylem
and phloem?
• What is the difference between nonvascular plants and vascular plants?
Origin of Plants
• Fossil evidence shows that green algae
are ancestors of plants today
Two Stages of Plant Life Cycles
• Sporophyte- produces spores
• Gametophyte- produces egg and
sperm cells
Section Two:
Plants Without Seeds
Pretty Flowers of the Day
Hydrangea
Black-Eyed Susan
Types of Seedless Nonvascular
Plants
• Keep in mind that non-vascular
plants do NOT have xylem and
phloem
• Three groups of Nonvascular
Plants
• Mosses
• Liverworts
• Hornworts
• All three groups are low-growing
and live in moist environments
• Sporophyte grows right
out of gametophyte
Mosses
• Most diverse group of
nonvascular plants (10,000
species)
• Rhizoid- thin, root-like
structure anchor mosses
and absorb water
• Spores produced in a
capsule at the top
Liverworts
• 8,000 species of liverworts
• Sporophyte named after the shape of
the human liver
Hornworts
• Less than 100 species of hornworts
• Live among grass
• Sporophyte looks like a horn
Seedless Vascular Plants
• Have vascular tissue
• Reproduce by spores
• Examples:
• Ferns
• Club Mosses
• Horsetails
Ferns
• 12,000 species
• Have true stems, roots,
and leaves
• Major part of the fern is
the frond
• Frond- leaves that
are divided into many
smaller parts that look
like small leaves
• Spores released from
underside of leaves
Frond
Horsetails
• Very few species left on Earth
• Very hard, bristly leaves
• Used by early Americans to clean
their pots and pans
Club Mosses
• Only a few hundred
species left on Earth
• Unlike true mosses,
these mosses do
have vascular tissue
• Looks like the small
branch of a pine tree
Ice Breaker
• What is the difference between xylem
and phloem?
• What is the difference between a plant
that is non-vascular and a plant that is
vascular?
Section 3: The Characteristics of
Seed Plants
What are Seed Plants?
• Seed plants are all around
you, and are very abundant
• For every 1 seedless
plant, there are 10 seed
plants
• Seed Plants
• Have vascular tissue
• Use pollen and seeds to
reproduce
• Have roots, stems, leaves
Review of Vascular Tissue
• Vascular tissuekeeps plants upright,
and supplies cells
with food, water, and
minerals
• Xylem- goes up,
carries water
• Phloem- goes down,
carries food
Ways of Reproduction
• Unlike seedless plants (i.e. moss),
seed plants can live in any
environment
• Seedless plants have to live in
moist environments
• Seed plants use the two following
structures to reproduce:
• Pollen- tiny structures that
contain cells that will be sperm
cells one day
• Seed- a structure that contains
a young plant inside a
protective covering that keeps
the plant from drying out
•
Seed
Structure
and
Dispersal
Inside of a seed is a partially
developed plant
• Three main parts:
• Embryo- the young plant that
develops from the zygote, or
fertilized egg
• Cotyledon- the leaves of a
seed; sometimes food is
stored in the cotyledon
• Seed Coat- outer covering
that protects the seed from
drying out
• Fruit- protects the whole seed
• What are the three ways in which
organisms move from place to
place?
• Seed Dispersal- Wind, water,
other organisms
•
Plant
Growth
Germination- occurs when
the seed begins to grow
again, and pushes out of the
seed
• It is best that a seed plants
itself away from its parent.
Can you think of why would
this be?
• Does not have to
compete with its parent
• Spreads its species out
over an area
• Can you imagine if all of
the pine trees in the
Adirondack region were
only located in the
schoolyard of
Northville?
Roots
• Three functions of roots:
• Anchor the plant
• Absorb water
• Store food
• Three types of roots
• Fibrous- dense and tangled;
take up a lot of space
• Examples: grass, onions,
corn
• Taproot- one big, massive root
that branches off into little
smaller hair-like roots
• Examples: dandelions, carrot
Fibrous
Tap Root
Structure of Roots
• Root Capprotects the root
from injury as the
root grows
through the soil
• Root Hairsincreases surface
area so that more
water and
minerals are
absorbed; also
helps to anchor
the plant better
Stems
• Stems- carries
substances between
plants roots and leaves;
holds leaves up towards
the sun
• Two types of stems:
• Herbaceous stemsoft (ex. Daffodils)
• Woody stem- hard
(ex. Maple tree, roses)
• Cambium- located
in woody stems that
is found towards
the outside; makes
new xylem and
phloem
Ice Breaker
• What are the three functions of roots?
• What is the cotyledon in a seed?
• What are the two ways of reproduction
in a seed plant?
•
Tree
Studies
Examine the following wood
samples…what do you see?
• Each ring represents one year
of growth
• Dendrochronology- the study
of tree growth by examining
annual rings
• Annual rings- circles in a
tree that represent how old
the tree is
• One dark ring and one
light ring make up one
full year
• Light ring- growth in
spring; really rapid
growth
• Dark ring- growth in
summer/fall; slower
growth
Summer/Fall
Spring
Leaves


Leaves- capture the sun’s
energy and carry out the
food-making process of
photosynthesis
Leaves vary greatly
depending on the tree



Oak trees have really big leaves
Pine trees have needles
Palm trees have leaves that are
big, but have small parts to it


Parts of a Leaf
Cuticle- prevents water loss
Stomata- pores that open and
close to control when gases
leave (O2) and enter the cell
(CO2)

Transpiration- the process by
which water evaporates from a
plant’s leaves



Stomata close during the day
to prevent transpiration from
the heat
Stomata open at night when
its cooler and there is less of a
chance of transpiration
Photosynthesis in Leaves

Photosynthesis occurs at the
top of the leaf, where there
are more chloroplasts
Section Four: Gymnosperm and
Angiosperms
Gymnosperms vs. Angiosperms
• Think of a pine cone versus
an apple
• Although they are
structurally different, they
both contain seeds
• Both are in different groups
• Gymnosperms- produces
“naked” seeds
• Seeds are not enclosed
within a fruit
• Trees tend to have needlelike leaves, and deep roots
• Example: pine tree,
spruce tree
Types of Gymnosperms
• Cycads- grow in subtropical
and tropical areas
• All plants about 175
million years ago were
cycads
• Conifers- cone-bearing
plants
• Largest and most diverse
of the gymnosperms
• Ginkgoes- only one living
tree today called Ginkgo
biloba
• Gnetophytes- live in dry
areas
• Can be either trees,
shrubs, or vines
• The plant Welwitschia can
live for 1,000 years
Reproduction in Gymnosperms
• Cones- the gymnosperm
reproductive structure that
can be either male or female;
covered in scales
• Trees usually have both
the male and female parts,
but some trees just have
one or the other
• At the base of each female
scale of a pinecone are
ovules
• Ovules- a structure that
contains an egg cell
• This will develop into a
seed once it is fertilized
Reproduction in Gymnosperms
• Steps of reproduction in a gymnosperm
are as follows…
• Step One: Pollination- pollen
transfers from the male structure to
the female structure
• Step Two: Fertilization- once the
sperm meets the egg cell, the ovule
closes off and seals it (the embryo
forms)
• Step Three: Seed Developmentfemale cones stay on the tree until
they get mature; males fall off of the
tree after they pollinate
• Step Four: Seed Dispersal- when the
seed is mature, the scales open up
and release the seed out into the air to
be picked up, carried to a new place,
and form into a new plant
Ice Breaker
• Roughly explain the reproductive cycle
of a gymnosperm
Pretty Flowers of the Day
Buttercup
Petunia
Angiosperms
• Angiospermsflowering plants that
have their seeds
enclosed within fruits
• Flower- the main
purpose of a flower is
for reproduction
• Carries reproductive
structures
• Attracts insects to
help pollinate
Parts of Flowers
• Sepal- located at the
base of the flower;
when the flower has
not bloomed yet, it is
contained within the
sepal
• Petals- colorful; this is
the main part that
attracts insects to the
flower for pollination
Male Parts of the Flower
• Stamen- male
reproductive part
• Anther- top
part where the
pollen is
produced
• Filament- thin
stalk where the
anther sits on
Female Parts of the Flower
• Pistil- female part of
the flower
• Stigma (“sticky
stigma”)- top
where pollen
sticks
• Style- long tube
where pollen
travels down to
fertilize ovaries
• Ovary- where the
egg and sperm
cells join; protects
the seed as it
grows
Reproduction in Angiosperms
• Pollination• Pollen from an anther falls
onto the “sticky stigma”
• The pollen then grows a
long tube down the style to
the eggs
• The sperm cells make their
way down to the egg cells
via the tube
• Fertilization- the sperm and
egg cells form (to make a
zygote) and then begin to
make an embryo within a
seed
• Fruit Development- as the
seed develops in the ovary,
the ovary then becomes a fruit
• Fruit- a ripened ovary that
protects seeds
Major Groups of Angiosperms
• Recall that cotyledons are the first leaves of
a seed, and a place where embryos can get
their food
• Monocots- “one cotyledon”
• Dicot- “two cotyledons”
Differences Between Mono and Dicots
Monocot
Plant
Part
Dicot
One
cotyledon
Seed
Two cotyledon
Parallel veins
Leaf
Branching
veins
Bundles of
Vascular
Tissue
Scattered
Stem
Vascular
Tissue
Bundles of
Vascular
Tissue in Ring
Flower
Flower Parts
in Fours or
Fives
Flower Parts
in Threes
Ice Breaker
• What is the cotyledon difference
between a monocot and dicot?
• What is the leaf differences between a
monocot and dicot?
• Explain the reproduction in an
angiosperm
Pretty Flowers of the Day
Tulip
Water Lily
Section 5: Plant Responses and
Growth
Tropisms
• Think of…
• Being pricked by a needle
• You try to move away from the
needle because it hurts
• Being really cold, and a fire in the
fireplace is burning in the next
room
• You move to the fire to warm up
• Both the needle’s pain and the fire’s
warmth is called a stimulus
• Tropism: a plant’s response toward
or away from a stimulus
Types of Tropisms Yum!
• Thigmotropism- a
plant’s response to
touch
• Example: vines
crawling up a wall,
Venus Fly Trap
• Phototropism- a plant’s
response to light
• Geotropism- a plant’s
response to gravity
Life Spans of Angiosperms
• Annual- flowers that complete
their life cycle in one year (only
live for one year)
• Examples- marigolds,
petunias
• Biennial- flowers that complete
their life cycle in two years (only
live for two years)
• Examples- Celery, foxgloves
• Perennials- flowers that live for
more than two years
• Example- Purple Coneflower,
Maple tree
Video
Plants and
People