Transcript gametophyte

Producers & Cellular Energy Notes
Unit 5
I can describe basic information about plants, including the way
they move material, are classified, reproduce, and evolved.
What are plants?
• Plants are members of the kingdom Plantae.
• Plants are multicellular eukaryotes that have cell
walls made of cellulose. They carry out
photosynthesis using the pigments chlorophyll a
and b.
What are plants?
• The first plants evolved from an organism much
like green algae.
What Plants Needs to Survive
• Sunlight – used to carry out photosynthesis
• Water and Minerals – plants need a continual
supply of water, and minerals, which come from
the soil.
• Gas Exchange – oxygen for cellular respiration
and carbon dioxide for photosynthesis
• Movement of Water and Nutrients – water is
absorbed in their roots but distributed
throughout the plant.
Groups of Plants
• Plants can be categorized as either vascular
plants, or non-vascular plants (called
bryophytes)
• Vascular plants have tracheids – specialized cells
that conduct water.
Figure 29.7
1 Origin of land plants (about 475 mya)
2 Origin of vascular plants (about 425 mya)
3 Origin of extant seed plants (about 305 mya)
Mosses
Land plants
ANCESTRAL
1
GREEN
ALGA
Nonvascular
plants
(bryophytes)
Liverworts
Hornworts
Pterophytes (ferns,
horsetails, whisk ferns)
3
Angiosperms
500
450
400
350
300
Millions of years ago (mya)
50
0
1 m
Seed plants
Gymnosperms
Vascular plants
2
Seedless
vascular
plants
Lycophytes (club
mosses, spike
mosses, quillworts)
Table 29. 1
1 m
The Plant Life Cycle
• Plant life cycles have alternating phases, called
alternation of generations, which alternates
between a haploid and diploid phase.
• The two cycles alternate to produce the two
types of reproductive cells – gametes and
spores/seeds.
Alternation of Generations
• The diploid (2N) phase is the
sporophyte – or spore/seed
producing plant.
• The haploid (N) phase is the
gametophyte – or gamete
producing plant.
Figure 30.2
PLANT GROUP
Mosses and other
nonvascular plants
Gametophyte Dominant
Sporophyte
Ferns and other seedless
vascular plants
Seed plants (gymnosperms and angiosperms)
Reduced, independent
(photosynthetic and
free-living)
Reduced (usually microscopic), dependent on surrounding
sporophyte tissue for nutrition
Reduced, dependent on
Dominant
gametophyte for nutrition
Dominant
Gymnosperm
Sporophyte
(2n)
Sporophyte
(2n)
Microscopic female
gametophytes (n) inside
ovulate cone
Gametophyte
(n)
Angiosperm
Microscopic
female
gametophytes
(n) inside
these parts
of flowers
Example
Gametophyte
(n)
Microscopic male
gametophytes (n)
inside pollen
cone
Sporophyte (2n)
Microscopic
male
gametophytes
(n) inside
these parts
of flowers
Sporophyte (2n)
Figure 29.8-3
“Bud”
Key
Haploid (n)
Diploid (2n)
Protonemata
(n)
“Bud”
Antheridia
Male
gametophyte
(n)
Sperm
Egg
Spores
Gametophore
Spore
dispersal
Female
gametophyte
(n)
Peristome
Sporangium
MEIOSIS
Mature sporophytes
Archegonia
Rhizoid
FERTILIZATION
Zygote (within archegonium)
(2n)
Seta
Capsule
(sporangium)
Foot
Embryo
2 mm
Archegonium
Capsule with
peristome (LM)
Young
sporophyte
(2n)
Female
gametophytes
1 m
Figure 29.9aa
Thallus
Gametophore of
female gametophyte
1 m
Marchantia polymorpha, a “thalloid” liverwort
Figure 29.9c
Polytrichum commune,
hairy-cap moss
Capsule
Seta
Sporophyte
(a sturdy
plant that
takes months
to grow)
Gametophyte
1 m
Figure 29.13-3
Key
Haploid (n)
Diploid (2n)
MEIOSIS
Spore
dispersal
Spore
(n)
Rhizoid
Underside
of mature
gametophyte
(n)
Sporangium
Sporangium
Antheridium
Young
gametophyte
Mature
sporophyte
(2n)
Sorus
New
sporophyte
Sperm
Archegonium
Egg
Zygote
(2n)
Gametophyte
Fiddlehead (young leaf)
1 m
FERTILIZATION
Figure 30.6-4
Key
Ovule
Haploid (n)
Diploid (2n)
Ovulate
cone
Megasporocyte (2n)
Integument
Pollen
cone
Microsporocytes
(2n)
Mature
sporophyte
(2n)
Megasporangium (2n)
Pollen
grain
Pollen
MEIOSIS
grains (n)
MEIOSIS
Microsporangia
Microsporangium (2n)
Surviving
megaspore (n)
Seedling
Archegonium
Female
gametophyte
Seeds
Food
reserves (n)
Sperm
nucleus (n)
Seed coat (2n)
Embryo
(new sporophyte)
(2n)
Pollen
tube
FERTILIZATION
Egg nucleus (n)
Figure 30.10-4
Mature flower on
sporophyte plant
(2n)
Microsporangium
Anther
Microsporocytes (2n)
MEIOSIS
Ovule (2n)
Ovary
Germinating
seed
MEIOSIS
Generative cell
Male
gametophyte
(in pollen
grain) (n)
Pollen
tube
Embryo (2n)
Surviving
megaspore
(n)
Endosperm (3n) Seed
Seed coat (2n)
Nucleus of
developing
endosperm
(3n)
Zygote (2n)
Antipodal cells
Central cell
Synergids
Egg (n)
Egg
nucleus (n)
Style
Pollen
tube
Sperm
(n)
FERTILIZATION
Key
Haploid (n)
Diploid (2n)
Tube cell
Pollen
grains
Stigma
Megasporangium (2n)
Female
gametophyte
(embryo sac)
Microspore (n)
Discharged sperm nuclei (n)
Sperm
Vascular Transport Systems
• Xylem – carries water upward from the roots to
every part of a plant.
▫ The main cells in the xylem tissues are the
tracheids.
• Phloem – transport solutions of nutrients and
carbohydrates produced by photosynthesis.
• Lignin – substance that makes cell walls rigid;
enables vascular plants to grow upright
Vascular Plant Structures
• Roots – underground organs that absorb water
and minerals.
• Leaves – photosynthetic organs that contains
one or more bundles of vascular tissue.
• Veins – made of xylem and phloem.
• Stems – supporting structures that connect roots
and leaves, carry water and nutrients.
Exit Slip
• What is the function of the xylem and the
phloem?
• Explain the difference between the gametophyte
and the sporophyte.
• What type of plant was the most primitive?
I can explain the critical parts of flowers and seeds, along with
their functions.
Warm-up
• What was the scientific name for nonvascular
plants?
• What are the names of the specialized cells that
conduct water?
Four Groups of Plants
Seedless Plants
Seed Plants
• Vascular (Ferns)
▫ Have xylem and phloem
• Gymnosperms (Conebearing Plants)
▫ Bear seeds directly on
their cones (non-enclosed
seed)
• Nonvascular
(Bryophytes/Mosses)
▫ Lack xylem and phloem
(conduct water via
osmosis)
• Angiosperms (Flowering
Plants)
▫ Bear seeds within a layer
of tissue that protects the
seed (enclosed seed)
Seed Plants
Gymnosperms
Angiosperms
• Includes four classes:
conifers, cycads,
ginkgoes, and
gnetophytes.
• Gymnosperms contain
structures called cones
that house their naked
seeds.
• Include grasses,
flowering trees, shrubs,
wildflowers, and other
flowers.
• Angiosperms contain
structures called flowers
that house their enclosed
seeds.
Gymnosperms
• Do not require water for reproduction – use the
wind mostly to transport pollen and seeds.
• Pollen Grains – contain the entire male
gametophyte in seed plants. Pollen grains are
transferred to the female gametophyte through the
process of pollination.
• Seeds – an embryo of a plant that is encased in a
protective covering and surrounded by a food
supply.
• Embryo – an organism in its early stage of
development
Gymnosperms
• Seed Coat – surrounds
and protects the
embryo—keeps the seed
from drying out.
Angiosperms
• Develop reproductive organs known as flowers,
which contain ovaries that surround and protect
the seed.
• After pollination, the ovary develops into a fruit
– a wall of tissue surrounding the seed. This
protects the seeds and aids in its dispersal.
Diversity of Angiosperms
• There are two classes within the angiopserms:
monocots and dicots/eudicots.
▫ Monocots and dicots are named for the number of
seed leaves, or cotyledons, in the plant embryo.
Monocots have one seed leaf, and dicots/eudicots
have two.
Figure 30.13ea
Monocot
Characteristics
Eudicot
Characteristics
Embryos
Two cotyledons
One cotyledon
Leaf
venation
Veins usually
netlike
Veins usually
parallel
Stems
Vascular tissue
scattered
Vascular tissue
usually arranged
in ring
Figure 30.13eb
Monocot
Characteristics
Eudicot
Characteristics
Roots
Taproot (main root)
usually present
Root system
usually fibrous
(no main root)
Pollen
Pollen grain with
one opening
Pollen grain with
three openings
Flowers
Floral organs
usually in
multiples of three
Floral organs
usually in multiples
of four or five
Plant Life Spans
• Annuals – are plants that complete a life in one
growing season.
• Biennials – complete their life cycle in two
growing seasons. In the first season, they germinate
and grow roots, short stems, and sometimes leaves.
In the second year, they grow new stems and leaves,
produce flowers and seeds, and die.
• Perennials – live for more than two growing
seasons.
Structure of Flowers
• Carpel (Pistil) – female
reproductive structure.
▫ Stigma – sticky tip; traps
pollen
▫ Style – slender tube;
transports pollen from stigma
to ovary
▫ Ovary – contains ovules;
ovary develops into fruit
▫ Ovule – contains egg cell
which develops into a seed
when fertilized
Structure of Flowers
• Stamen – male reproductive
structure
▫ Filament – thin stalk;
supports anther
▫ Anther – knob-like
structure; produces pollen
▫ Pollen – contains
microscopic cells that become
sperm cells.
Structure of Flowers
• Sepals – encloses and
protects flower before it
blooms
• Petals – usually colorful and
scented; attracts pollinators
Exit Slip
I can explain how cells store energy as ATP.
Energy and Life
• Energy – the ability to do work.
▫ Autotrophs – organisms that make their own food.
▫ Heterotrophs – organisms that cannot use the sun
or earth’s energy directly, thus they obtain energy
from the foods they consume.
• Chemical Energy – stored within chemical
bonds and is released when these bonds are
broken.
ATP
• Adenosine Triphosphate (ATP) – the
energy molecule used to complete work in cells.
▫ Consists of adenine, ribose (5-carbon sugar), and
3 phosphate groups
▫ The 3 phosphate groups are the key to ATP’s
ability to store and release energy.
ADP
• Adenosine Diphosphate (ADP) – a
compound similar to ATP, except it has 2
phosphate group.
ATP and Glucose
• ATP is a great molecule for transferring energy,
but not good for storing large amounts of energy
for a long time.
• To store energy for long periods of time, the cell
relies on carbohydrates, like glycogen animals
and starch in plants.
▫ Both glycogen and starch are polymers made of a
smaller simple-sugar monomer called glucose,
which has 90x the chemical energy of ATP.
Exit Slip
I can represent photosynthesis, fermentation, and cellular
respiration using a chemical formula.
Photosynthesis
• Photosynthesis – the process where plants use
the energy from sunlight to convert water and
carbon dioxide into high energy carbohydrates,
such as sugars and starch, and oxygen gas, a
waste/byproduct.
Van Helmont’s Experiment
• 1600s – Van Helmont plans experiment to
find if plants grow by material from the soil.
• He determined that mass of a pot of soil and
seedling and planted the seedling in the soil and
watered regularly for 5 years.
• The seedling grew into a small tree and now weighed
about 75 kg, but the mass of the soil was almost
unchanged.
• Van Helmont concluded that most of the gain of
mass had come from water, as that was the only
thing he had added.
Priestley’s Experiment
• 1700s – Priestley took a candle, placed a
glass jar over it, and watched as the flame
gradually died out.
• Priestley reasoned something in the air was
necessary to keep the flame burning, and when this
substance ran out, the candle went out. The
substance was ______.
• Priestley found that if he placed a live sprig of mint
under the jar and allowed a few days to pass, the
candle would remain lit for a while. The mint had
produced the substance required for
burning.
Ingenhousz Experiment
• Later, Ingenhousz showed that the effect
observed by Priestley only occurred when the
plant was exposed to light. The result of
Priestley and Ingenhousz’s experiments showed
that light is necessary for plant to produce
O2 .
• These early experiments led other scientists to
discover that in presence of light, plants
transform carbon dioxide and water into
carbohydrates and they also release oxygen.
The Photosynthesis Equation
• Photosynthesis used the energy of sunlight to
convert water and carbon dioxide into high energy
sugars and oxygen. Plants use the sugars to produce
complex carbohydrates such as starches. Plants
obtain carbon dioxide from the atmosphere.
I can explain the interaction between pigments, absorption of
light, and reflection of light.
Light and Pigments
• Photosynthesis requires 4 components:
1.
2.
3.
4.
Carbon dioxide
Water
Light
Chlorophyll (pigment)
• Energy from the sun travels to Earth in the form
of light, which plants gather with light-absorbing
molecules called pigments.
• The plants main pigment is called chlorophyll.
▫ Two types: Chlorophyll a and b
Figure 10.7
105
nm 103 nm
103
1 nm
Gamma
X-rays
rays
UV
nm
1m
(109 nm)
106 nm
Infrared
Microwaves
103 m
Radio
waves
Visible light
380
450
500
Shorter wavelength
Higher energy
550
600
650
700
750 nm
Longer wavelength
Lower energy
Chlorophyll Absorption
Spinach Chromatography
Exit Slip
I can describe the light-dependent and light-independent
reactions (Calvin cycle) of photosynthesis and related the
reactants and products of each reaction.
The Reactions of Photosynthesis
• Photosynthesis takes place inside chloroplasts.
• Within the chloroplast, there are saclike
photosynthetic membranes called thylakoids,
which are arranged in stacks known as grana.
• Proteins in the thylakoid membrane organize
chlorophyll and other pigments into clusters
known as photosystems, which are the lightcollecting units of the chloroplast.
Figure 10.4a
Leaf cross section
Chloroplasts Vein
Mesophyll
Stomata
Chloroplast
CO2
O2
Mesophyll
cell
20 m
Figure 10.4b
Chloroplast
Outer
membrane
Stroma
Thylakoid
Granum
Thylakoid
space
1 m
Intermembrane
space
Inner
membrane
The Reactions of Photosynthesis
• Photosynthesis unfolds in two parts: the lightdependent reactions and the light-independent
reactions, also known as the Calvin cycle.
• The light-dependent reactions take place within
the thylakoid membranes. The Calvin cycle
takes place in the stroma – the region outside
the thylakoid membranes.
Figure 10.6-4
CO2
H2O
Light
NADP
ADP
+ Pi
Light
Reactions
Calvin
Cycle
ATP
NADPH
Chloroplast
O2
[CH2O]
(sugar)
Figure 10.14-5
4
Primary
acceptor
2
H
+
1/ O
2
2
H2O
e
2
Primary
acceptor
e
Pq
7
Fd
e 
e
Cytochrome
complex
8
NADP
reductase
3
Pc
e
e
P700
5
P680
Light
1 Light
6
ATP
Pigment
molecules
Photosystem II
(PS II)
Photosystem I
(PS I)
NADP
+ H
NADPH
The Light Reactions
Figure 10.19-3
Input
(Entering one
CO2 at a time)
3
Phase 1: Carbon fixation
Rubisco
3 P
Short-lived
intermediate
P
6
P
3-Phosphoglycerate
P
3P
Ribulose bisphosphate
(RuBP)
6
ATP
6 ADP
3 ADP
3
Calvin
Cycle
6 P
P
1,3-Bisphosphoglycerate
ATP
6 NADPH
Phase 3:
Regeneration of
the CO2 acceptor
(RuBP)
6 NADP
6 Pi
P
5
G3P
6
P
Glyceraldehyde 3-phosphate
(G3P)
1
P
G3P
(a sugar)
Output
Glucose and
other organic
compounds
Phase 2:
Reduction