Download Seed Plants - Gymnosperms

Name ________________________________Bio 126 Plant Groups Lab
Field identification characters:
1. Moss/ Liverworts
The term bryophytes does not refer to a taxonomic category; rather, bryophytes are
an ancient group of plants that appear to have evolved into several different groups
independently and did not give rise to any other living groups of plants. They are
small plants generally lacking vascular tissue (specialized cells for the transport of
material), although water-conducting tubes appear to be present in some mosses.
(However, these tubes may be unrelated to the vascular tissue in vascular plants.)
The life cycle for the bryophytes differs from all other land plants because the
gametophyte is the dominant and conspicuous plant. Because bryophytes are
nonvascular, they are restricted to moist habitats and have never attained the size of
other groups of plants. The gametophytes remain close to the ground, enabling the
motile sperm to swim from the antheridium to the archegonium and fertilize the
egg. Some parts of the plants are covered with a thin cuticle layer, possible more
important for uv light protection than water loss. They lack stomata on the surface of
the thallus (plant body), which is not organized into true roots, stems, and leaves.
Bryophytes are not important economically, with the exception of sphagnum moss,
when harvested and dried is known as peat moss. Peat moss is absorbent, has
antibacterial agents, and was reportedly once used as bandages and diapers.
Today peat moss is used primarily in the horticultural industry and is primarily
collected in Canada. Over the millennia, large peat bogs have formed which trap
tons of organic carbon. In Ireland the partially decomposed peat is still harvested as
a fuel. Other types of Irish moss are used as a preferred flavoring agent in brewing
many specialty beers.
2.
What is a spore?
In order to complete its lifecycle, what do the Moss & Liverworts use for
gametes?
What do liverworts look like ?
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 LABEL A LL THE STRUCTURES OF THE MOSS LIFE CYCLE. INCLUDE: SPORE,
PROTONEMA, GAMETOPHORE (“BUD”), MALE GAMETOPHYTE, FEMALE
GAMETOPHYTE, RHIZOIDS, PHYLLIDIA (“LEAVES”), ARCHEGONIA, EGG,
ANTHERIDIA, SPERM, ZYGOTE, SPOROPHYTE, SPORANGIA, SETA, CAPSULE,
SPORES
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3.
Ferns / Equisetum
These two groups have been classified as separate phyla in the past, the
Sphenophyta Horsetails (Equisetum spp’) and the Psilophyta Whisk ferns
(Psilotum spp.). But after recent molecular studies, they are often now put in
with the ferns (as does our text) as new classes in one larger phylum Pterophyta.
We will have samples of Horsetail and ferns to view..
Ferns have several derived features that ahs allowed them to move farther away
from the limited environments of their bryophyte ancestors. Most significantly in
the sporophyte phase they have vascular tissues, xylem to conduct water up
from their roots and phloem to carry sugars throughout the plant. The
gametophytes lack these tissues. The sporophytes form true roots that draw
water up from deep in the soil and leaves with tissues to distribute the excess
sugar to the rest of the plant. The woody sporophyte has become the dominant
and perennial phase, able to produce spores in its sporangia for years. The
leaves are called fronds, and increasing from their ends, unraveling as they
grow. These thick leaves have stomata to allow for gas exchange. Sporangia
are typically clustered on the underside of fronds in groups called sori. Each
sporangium has a thick ridge of cells called an annulus that dries out, shrinking
back and forcibly ripping open the sporangial wall throwing the spores out into
the air currents.
Ferns still need a film of water to sexually reproduce, because the
hermaphroditic gametophyte produces swimming sperm. The gametophyte
lacks vascular tissues and must have a moist environment long enough for the
sporophyte to form.
LABEL ALL THE STRUCTURES OF THE FERN LIFE CYCLE. INCLUDE: SPORE, YOUNG
GAMETOPHYTE, MATURE GAMETOPHYTE (PROTHALLIUM), RHIZOIDS, ARCHEGONIA,
EGG, ANTHERIDIA, SPERM, ZYGOTE, SPOROPHYTE, FRONDS ( LEAVES), ROOTS,
SORUS, SPORANGIA, ANNULUS, SPORES
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What are their leaves called?
What is found on the underside of the leaves?
What allows the plant to survive in drier areas than the mosses?
What is Wood?
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SEED PLANTS - GYMNOSPERMS
– Pines and other cone bearing trees
The term gymnosperms refers to a diverse group of seed plants that do not produce
flowers, but do produce pollen and seeds.
The largest and best known gymnosperm division is Coniferophyta, which includes pines,
redwoods, cypresses, junipers, other cone-bearing trees and shrubs. Many have thick
needle shaped leaves with a thick cuticle layer. The needles group in groups called
fascicles. Counting the number of needles per fascicle is one feature used to identify
different pine species. Many conifers grow at high elevations with freezing winters that
other trees can not tolerate.
PINE LIFE CYCLE
 Label the Pine Life cycle.
o Include: Meiosis, Mitosis, Fertilization, Sporophyte embryo, female
gametophyte tissue, male (staminate) cone, female (ovulate) cone, ovule,
microspores, megaspore, ovule, pollen grain, archegonium, egg, pollen
tube, micropyle/integuments.
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4.
Gymnosperms: “naked seeds”
Cones:
Pines- draw a pine cone as it would appear on a branch.
What does Closed-Cone Pine mean?
Needles: compare pines
a.
3 per fassicle, vs. 5 per fassicle
b.
redwood leafy-scales
c.
cypress scales
Angiosperms – flowering plants
a.
What have the parts of the flower coevolved with?
b.
Draw and label the parts of a flower.
c.
How can you tell a monocot from a dicot flower?
d.
What have fruit structures co-evolved with?
Flower Morphology
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You will investigate the structure of the flower. You will need to take apart each flower
carefully to determine its structure, and write its floral formula. You may be able to
determine the floral traits for large, open flowers by simply observing. However, most
flowers will require that you remove the floral structures from the outside toward the
center of the flower. Some flowers or structures may require the use of the dissecting
microscope. For example, the ovary is positively identified by the presence of tiny
crystal-like ovules, and these are best seen with the dissecting scope.
Floral Parts
Pedicel:
stalk that supports the flower.
Receptacle:
tip of the pedicel where the flower parts attach.
Sepal:
outer whorl of bracts, which may be green, brown, or colored like the
petals; may appear as small scales or be petal-like.
Calyx:
all the sepals, collectively
Petal:
colored, white, or even greenish whorl of bracts located just inside the
sepals.
Corolla:
all the petals, collectively
Stamen:
pollen-bearing structure, composed of filament and anther.
Filament:
thin stalk that supports the anther.
Anther:
pollen-producing structure.
Carpel:
female reproductive structure, composed of the stigma, style, and ovary,
often pear-shaped and located in the center of the flower.
Stigma:
receptive tip of the carpel, often sticky or hairy where pollen is placed;
important to pollen germination.
Style:
tissue connecting stigma to ovary, often long and narrow,
but may be short or absent; pollen must grow through this tissue to
fertilize the egg.
Ovary:
base of carpel; protects ovules inside, matures to form the
fruit.
Regular:
A symmetrical arrangement of flower parts. Sepals and petals are all of the
same size, shape and color, and they are arranged uniformly around the
receptacle. Also called actinomorphic.
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Irregular:
An asymmetrical bilateral arrangement of flower parts.
Sepals and petals are all of the unequal size, shape and color, and they
are not arranged uniformly around the receptacle. Also called
zygomorphic.
Bilabiate:
An irregular “two-lipped” flower in which calyx and / or the
corolla appears to be in two parts. One part facing upward as a flag or
banner. The second faces forward for a landing platform and then down.
Using
preceding
the
terms,
label
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the
diagram
of
a
Dicot
Flower
Leaves
What is simple vs. compound leaf ?
Draw a twice pinnately compound leaf :
Draw leaf margins: entire, toothed, wavy, lobed
Draw Opposite vs. Alternate leaf placement on the stem :
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SIMPLE KEY TO POLLINATORS
1) Sepals and petals reduced or inconspicuous; feathery or relatively large stigma;
flower with no odor
WIND
2) Sepals and/or petals large, easily identified; stigma not feathery; flower with or
without odor
A) Sepals and petals white or subdued (greenish or burgundy); distinct odor
i) Odor strong, heavy sweet released at night
MOTH
ii) Odor strong, fermenting or fruitlike released at night; flower parts and pedicel
thick, strong
BAT
iii) Odor of sweat, feces, or decaying meat released during the day
FLY, WASP
B) Sepals and/or petals colored; odor may or may not be present
i) Flower shape not tubular
(1) Flower shape irregular; sepals or petals blue, yellow, or orange; petal
adapted to serve as a “landing platform”; may have dark lines on petals;
sweet, fragrant odor
BEE
(2) Flower shape regular; odor often fruity spicy sweet, or carrion like
BEETLE
ii) Flower shape tubular
Strong, sweet odor, flat –topped narrow head of flowers with room for wings
BUTTERFLY
(1) Little or no odor; flower pendulous, usually red
HUMMINGBIRD
What is the Pollinator for the:
Fuchsia ____________
Snapdragon _________
Scabiosa _____________
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VIDEO: SEXUAL ENCOUNTERS OF THE FLORAL KIND
1. Hammer Orchid and Atheid Wasp
a. Why does the flower appear before the females wasps emerge?
b. What reward does the orchid offer its pollinator? Do the wasps benefit?
2. African Water Lilly
a. What happens on day two?
b. What happens on day one? Are the anthers open?
3. Sardinian Kidnapping Lilly
a. What reward does this flower offer the flies? Do the flies benefit?
b. Why is it essential some flies escape?
4. Mammalian Pollinators
a. What reward does this flower offer the mammals?
b. Give some examples of the pollinating mammals
5. Arctic Primrose
a. What reward does the primrose offer its pollinator? Do they benefit?
6. Water Plant
a. Where do the flowers form?
b. How does it get pollinated?
7. Rainforest Tree Orchid
a. What reward does the orchid offer the male bees? Do they benefit?
b. Why does the orchid trap the bees?
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