Transcript of Plants Kingdom: Plantae Sporophytes are diploid and gametophytes are haploid. Review Photosynthesis...
- Slide 1
- Plants Kingdom: Plantae Sporophytes are diploid and
gametophytes are haploid. Review Photosynthesis and Cellular
Respiration Plant provide the base for food chains on land. They
also provide shade, shelter and oxygen for animals.
- Slide 2
- Plant Life Cycle Plant life cycle has 2 alternating phases, a
diploid (2N) phase and a haploid (N) phase. This is known as
alternation of generations. Mitosis and meiosis alternate to
produce the 2 types of reproductive cells which are the spores and
gametes. Diploid (2N) phase is known as the sporophyte or spore
producing plant. Haploid (N) phase is known as the gametophyte or
gamete producing plant.
- Slide 3
- Plant Life Cycle Plant spores are haploid (N) reproductive
cells formed in the sporophyte plant by meiosis that can grow into
new individuals is the gametophyte. Gamete is a reproductive cell
that is produced by mitosis and fuses during fertilization with
another gamete to produce a new individual, the diploid sporophyte.
The earliest type of plants, mosses and ferns, required water to
reproduce. Seed plants have evolve reproductive cycles can be
carried out without water. Many plants have forms of vegetative or
asexual reproduction. See Figure 22-2
- Slide 4
- Movement of H 2 O and Nutrients Plants takes up water and
mineral through their roots and make food in their leaves.
Specialized tissues carry water and nutrients upward from the soil
and distribute the products of photosynthesis throughout the plant
body. Simpler types of plants carry out these function by
diffusion.
- Slide 5
- Early Plants The first plant evolved from an organism much like
the multicellular green algae living today. Land plants evolved
from green algae. Early plants evolved structures that acquire,
transport, and conserve water. Green algae have cell walls and
photosynthetic pigments that are identical to those of plants. They
have chlorophyll that captures energy from the sunlight during
photosynthesis. Both use starch as a storage product
- Slide 6
- Early Plants Most green algae have cell walls made of cellulose
which is found in the cell wall of all plants. Evidence from
genetic analysis points to an ancient species of green algae that
is the common ancestor of all plants. Today the species would be
classified as a member of the class Charophyceae. Today,
charophyceans are common in freshwater habitats. Ancestral
charophycean species may have grown in shallow water the dried out
from time to time
- Slide 7
- Early Plants Several important plant characteristics likely
originated in the charophyceans are: 1. multicellular body, which
lead to specialize cells and tissues 2. Cell division which
produced cells with small channels in their walls 3. Reproduction
where the sperm travels and fertilize an egg cell. True plants have
multicellular embryos that remain attached to the female parent as
they develop
- Slide 8
- Early Plants The earliest plant fossil date to more than 450
million years ago. The first true plant grew on the edges of lakes
and streams. They relied on droplets of water that bought sperm to
eggs to produce the next generation of plants. Their structure was
similar to moss, keeping low to the ground to retain moisture.
Descendants were able to live in even drier areas
- Slide 9
- Early Plants Fossils suggest the first true plant depended on
water to complete their life cycles. The evolved of plants are more
resistant to the drying sun. These plants are capable of conserving
water and reproduce without water.
- Slide 10
- Plant Adaptation for Land Algae is constantly surrounded by
water which is needed for photosynthesis. The buoyancy of water
supports the weight of most algae. Water provides the medium
through which the sperm and spores can travel, allowing for
reproduction and dispersal. Water prevents sperm, eggs, and the
developing offspring from drying out.
- Slide 11
- Plant Adaptation for Land The challenges of living on drier
land acted as selective pressures for plants. Plants evolved
adaptations that allowed them to retain moisture, transport water
and other resources between plant parts, grow upright, and
reproduce without free standing water.
- Slide 12
- Plant Adaptation for Land Retaining Moisture The surfaces of
plants are covered with a cuticle. A cuticle is a waxy, waterproof
layer that helps hold in moisture. The are tiny holes in the
cuticle called the stomata. Special cells that allow stomata to
close to prevent water loss or to open to allow air to move in and
out. Without the stomata the movement of air would be prevented by
the cuticle.
- Slide 13
- Transporting Resources Taller plants has better access to
sunlight and CO 2 from the air but they must get water and
nutrients from the soil. A structure for moving the resources to
different parts of the plant evolved in the form of a vascular
system. Vascular system is specialized tissue that bring water and
mineral nutrients up from the roots and disperse the sugar from the
leaves. This system allows a plant to grow higher off the
ground
- Slide 14
- Plants Growing Upright Lignin a substance which hardens the
cell wall of some vascular tissues. Lignin also strengthens wood
and provides stiffness the stems of other plants. Lignin allows to
retain their structure as they grow toward the sun.
- Slide 15
- Reproducing on Land Eggs are fertilized within the tissue of
the parent plant. The fertilized egg develops into an embryo. Some
plants use raindrops or dew for reproduction. Other plants do not
need free standing water for reproduction. These plants have
adaptations that allow seed plants to reproduce. Pollen grain is a
2 celled structure that contain a cell that will divide to form a
sperm. This pollen can be carried by the wind or animals to a
female structure.
- Slide 16
- Reproducing on Land Seed is a storage device for a plant
embryo. The seed has a hard coat to protect it from drying wind and
sunlight. When the conditions are right, the embryo can develop
into an adult plant.
- Slide 17
- Mutualism Mutualism in interaction between 2 species where both
of the species are benefiting. Example: plants roots and fungi and
bacteria The roots provide a habitat for the fungi and bacteria
while the fungi and bacteria helps the plant to get nutrients from
the soil. Flowering plants depends on the animal species for
pollination or seed dispersal. The animals are fed by the pollen,
nectar or fruit.
- Slide 18
- Plant-Herbivore Interactions Plants have a variety or
adaptations to keep animals from eating them. Plants have spines,
thorns and chemical that act as pesticides against plant eating
predators. The larvae of monarch butterflies, feed on milkweed
species. Milkweed plants produce a chemical that makes the monarch
larvae, adults, and even eggs taste bad to predators. The butterfly
has a chemical protection as a result of eating the milkweed leaves
during its development.
- Slide 19
- Fruits and Seed Dispersal Biologically, a fruit is a flowers
ripen ovary which surrounds and protects the seed or seeds. Fleshy
fruits are tasty food sources for animals, which digest the fruit
tissue but not the seeds. Seeds pass through the animal and are
deposited along with a supply of fecal fertilizer that helps during
germination. Others may cling to wildlife or fibers that help
spread seeds by wind.
- Slide 20
- Flowers and Pollination Flowers have more efficient pollination
than gymnosperms which relies on the wind for pollination. Animal
pollinators transfer pollen from flower to flower in a very
targeted way. Therefore; flowering plants pollinated by animals
dont need to produce nearly as much pollen as the plants that rely
on wind to randomly transfer the pollen.
- Slide 21
- Classifying Flowering Plants Flowering plants are classified
into 2 groups based on 2 basic kinds of seed: seeds with one or two
cotyledons Cotyledon is an embryonic leaf inside a seed. They are
often called seed leaves. As embryo develop, the seed leaf may
remain inside of the seed while others may break our of the seed
and turn green.
- Slide 22
- Monocot Monocots are flowering plants whose embryo has one seed
leaf. Monocots plants have parallel veins in long, narrow leaves,
like those in an iris of lily. Their flower parts occur in
multiples of 3, and bundles of vascular tissues are scattered
throughout the stem. Cereals plants such as corn, wheat, and rice.
Also grasses, irises, and lilies.
- Slide 23
- Dicots Dicots are flowering plants that have 2 seed leaves.
Dicots have leaves with netlike veins. The flowers are in multiples
of 4 or 5 and bundles of vascular tissue are arranged in rings.
Deciduous trees that lose their leaves in the Fall are dicots.
Peanuts are dicots.
- Slide 24
- Herbaceous or Woody Stems Wood is a fibrous material made up of
the vascular system of some plats. High concentration of lignin and
cellulose make the cell walls of these cells thick and stiff. Vines
have woody stems. Plants that do not produce wood, such as
cucumbers and marigolds are called herbaceous plants.
- Slide 25
- Three Types of Lifespans Annual flowering plants mature from
the seed, produce flowers, and die all in one year. Ex. Corn and
lettuce Biennial flowering plants that take 2 years to complete
their life cycle. The first year they produce a short stem leaves
that grow close to the ground and underground food reserves. During
the second year, a taller stem, leaves, flowers, and seeds. Ex.
Carrots Perennial- any flowering plant that lives for more than 2
years. Ex. Trees or die and grow back in the spring.
- Slide 26
- Type of Plant Cells Plants cell have the same organelles as an
animal cell plus cell wall, plastids and a large vacuole.
Parenchyma thin wall and water filled vacuole in the middle. Found
throughout a plant. It stores starch, oils, and water for the
plant. Photosynthesis takes place in the green chloroplast within
the parenchyma cells in the leaves. Chloroplast and colorless
plastids in parenchyma cells within roots and stem store starch.
They divide their entire lives and helps with healing or
regenerating new parts.
- Slide 27
- Types of Plant Cells Collenchyma Cell has cell wall that range
from thin to thick, providing support while allowing a plant to
grow. Cells are found in younger tissue of leaves and shoots. The
unique feature is the cells are flexible. The cells can elongate
and still give the leaf structure. Sclerenchyma Cells is the
strongest type of cell. They have a 2 nd cell wall which contains
lignin making the cells very tough and durable. When the cell dies
the dead cell disintegrate but the rigid cell wall is left behind
as skeletal support of the water-conducting tissue for the plant.
Sclerenchyma forms the fruit pit and the harder outer shell of
nuts. Cells make linen and rope.
- Slide 28
- Three Tissue Systems The plasmodesmata is the system that
connects neighboring cells where cytoplasm that pass through
openings in cell walls and connect living cells. The cells can
share water nutrients, and chemical signals.
- Slide 29
- Three Tissue Systems Dermal Tissue System covers the outside of
a plant and protect in a variety of ways. Dermal tissue epidermis)
is made of live parenchyma cells in the nonwoody parts of the
plants. Epidermal cells secrete a wax-coated substance that becomes
the cuticle. Dermal tissue made of dead parenchyma cells makes up
the outer bark of woody plants.
- Slide 30
- Three Tissue Systems Ground Tissue System makes up much of the
inside of a plant. It provides support and stores materials in the
roots and stems. The ground tissue in leaves is packed with
chloroplast for photosynthesis. Ground tissue consist of all 3
simple tissue types: parenchyma tissue, collenchyma tissue, and
sclerenchyma tissue. Parenchyma is the most common in ground
tissue.
- Slide 31
- Three Tissue Systems Vascular Tissue System transport water,
minerals nutrients, and organic compounds (sugars) to all parts of
the plant. The vascular system is made up of 2 networks of hollow
tubes somewhat like our arteries and veins. Each network has a
different type of vascular tissue to move different resources
throughout the plant.
- Slide 32
- Three Tissue Systems Xylem is the vascular system that carries
water dissolved mineral nutrients up from the roots to the rest of
the plant. Xylem contains other types of cells so it is called a
complex tissue Phloem is the vascular tissue that carries the
products of photosynthesis through the plant.
- Slide 33
- The Vascular System Tracheid is a long narrow specialized cell
in the xylem. Water can flow from cell to cell through openings in
the thick wall. Vessel elements are specialized cells in xylem.
They are shorter and wider than tracheids. When the vessel elements
die, the cell wall disintegrates at both ends. The cell connect end
to end and forms a long tube.
- Slide 34
- The Vascular System Cohesion-tension theory the physical
properties of water allow the rise of water through the plant
without metabolic energy. The theory is based strong attraction of
the water molecule to one another and to other surfaces. The
tendency for hydrogen bonds to form between water molecules creates
a force called cohesion.
- Slide 35
- Slide 36
- Plant Kingdom Four groups based on 3 features: 1. Water
conducting tissues 2. Seeds 3. Flowers 4. Reproductive structures
The first plant evolved from a green algae living in fresh water
not in the sea as once thought. Flowering plants have 235,000
species.