Transcript spermatophytes

AKA Gymnosperms and Angiosperms
Seeded vascular plants evolved more than 200 million years ago.
When evolving a more terrestrial lifestyle, there were some
very obvious hurdles to overcome:
• Structural Support
•Transport of materials
• Fertilization without water
• Seed disbursal
Plants that reproduce by means of
seeds do not necessarily require
abundant moisture in order to complete
their life cycle. The fertilization, as
well as seed disbursal of gymnosperms
and angiosperms relies on wildlife, as
well as wind and water!
The spermatophytes, which means
"seed plants", are some of the most
important organisms on Earth. Life
on land as we know it is shaped
largely by the activities of seed
plants. Soils, forests, and food are
three of the most apparent
products of this group
As a result of all these adaptations,
seed plants are able to grow in
much drier habitats than are plants
that do not have seeds or vascular
Male and female cones
tissue.
The seeds from coniferophytes are found look quite different.
within specially adapted cones, which are
disbursed largely through the help of animals.
As with the simpler plants,
there is a sporophyte and
gametophyte generation in
seed plants.
• male and female cones
Monoecious
• microspore/megaspore
• pollen to archegonium
• fertilization (2N)
• seed dispersal
• germination
• sporophyte
Both genders are present
on one plant…
The flowering plants
represent the most
complex of all seed
plants.
They have many
adaptations to help
spread their pollen.
Some angiosperms
produce not only
flowers, but fruit as
well.
A fruit is nothing more than a ripened ovary, with the
accompanying seeds within.
Fruits represent a dispersal method that some flowering plants
have adapted.
Fruits (in either sense of the word) are the means by which
many plants disseminate seeds. Most plants bearing edible
fruits, in particular, coevolved with animals in a symbiotic
relationship as a means for seed dispersal and nutrition,
respectively; in fact, many animals have become dependent on
fruits as a source of food. They are known as “frugivores”.
Mutualism
What type of symbiotic relationship?
Many times,
when fruits are
consumed, the
seeds are left
behind as a
waste of the
animals. The
plants benefit
because it helps
them to
disseminate
their seeds…
Again, with
angiosperms,
there is an
alternation
between
sporophyte and
gametophyte
generations.
• micro and
megaspore
production within
male and female
flower parts
• pollination
• fertilization
• germination of
sporophyte
The tiny epicotyl is the
embryonic plant shoot just
starting to grow.
The hypocotyl is the stemlike embryonic structure
below the epicotyl
The radicle will become the
root of the developing embryo
The seed coat, also called the
“testa” is the outer membrane
of the seed, which serves to
protect the seed from the
environmental conditions.
The endosperm is the
nutrient for the developing
seedling (stored starch)
The cotyledon, or seed leaf is
what will eventually become
the leaves of the plant.
Monocots:
• Embryo with a single cotyledon
• Flower petals in multiples of
three • Major leaf veins are parallel
• Vascular
bundles are
scattered
throughout stem
• Embryo with
two cotyledons
Eudicots:
• Flower
petals in
multiples of
four or five
• Major leaf veins are netted
• Vascular bundles arranged in a ring
Tomorrow, you’ll be going out into the field.
You’ll be finding examples of monocots and
eudicots, based on their structure, for part B
of the transpiration lab. In your lab group:
• Find one example of each, and pick it.
• Bring inside and put in large beaker for tomorrow
• Sketch each of your chosen plants in your
quadrille, identifying it as a monocot or eudicot
based upon its structure
• Prepare part B pre-lab for tomorrow