Transcript Survey of the Phyla- Plantae IION

Kingdom Plantae Part II
Seed plants-produce seeds in the sporophyte generation. A
seed consist of a seed coat, food, and sporophyte embryo.
Also spores produced by the sporophyte generation are
retained in the plant and are not released into the
environment. All seed plants produce two different types of
spores (heterospory). Microspores make the male
gametophyte (pollen) and megaspores make the female
gametophyte inside a structure called the ovule. The female
gametophyte never leaves the sporophyte. The ovule
eventually becomes the seed once the egg of the female
gametophyte is fertilized. Note-sperm cells are not released
into the environment like seedless plants. The entire male
gametophyte is used to deliver the sperm cells. Seeds and
pollen eliminates the necessity of water for reproduction.
Both can be carried long distances and have a thick coats to
resist drying out.
Which of the following is true?
A) Whisk ferns lack vascular tissue.
B) Whisk ferns have megaphylls.
C) True ferns have megapylls.
D) Rhizoids are true roots.
ANS: C
Whisk ferns have vascular tissue and
true roots. Rhizoids are not true
roots rather they are not tissue but
just extensions of cells. True ferns
have true leaves or megaphylls.
Two major types of seed plants-Gymnosperms and
angiosperms. Gymnosperms produce naked seeds (ovule
not complete enclosed in sporophyte tissue). Does not
produce fruit or flowers.
Gymnosperms
Conifers-Largest gymnosperm group 575 species most do
not shed their leaves in the fall. Includes pine tree, junipers
and sequoias. It takes 2 yrs to produce a seed.
Which of the following would not be
found in a seed?
A) fruit
B) Food
C) Embryo
D) seed coat
ANS: A
Fruit arises from the ovary, which is
found outside the seed. Seeds have a
seed coat, food and fruit.
What is the difference between the seed
of a gymnosperm and the seed of an
angiosperm.
A) The seed of an angiosperm is diploid and
the seed of a gymnosperm is haploid.
C) The seed of an angiosperm is surrounded
by tissue from ovary (fruit) and the seed
of a gymnosperm is not.
B) The seed of an angiosperm is comes
from a megaspore and the seed of a
gymnosperm comes from a microspore.
D) The seed of an angiosperm is a
gametophyte and the seed of a gymnosperm
is a sporophyte.
ANS: C
The seed of an angiosperm is
surrounded by tissue from ovary
(fruit) and the seed of a gymnosperm
is not. That is why the seeds of the
gymnosperm are called “naked seeds”.
Other gymnosperms
Phylum Cycadophyta-cycads have large cones and palmlike
leaves.
Phylum Ginkgophyta-only one species surviving. Diciduous
fan leaves with fleshy seeds.
Phylum Gnetophyta-species are found in tropics and desert
and varies greatly in morphology.
Phylum Anthophyta-Flowering plants
Characteristics-flowers and the production of seeds. Most
successful plant phylum. A flower is a structure specialized
for reproduction.
1. Sepal-leaf like and protects the floral bud.
2. Petals-Usually showy with colors to attract pollinators
3. Stamen-male reproductive organ. Contains an anther
where male gametophytes or pollen is produced. The anther
sits long stalk called the filament, which connects to the base
of flower
4. Carpel-female reproductive organ. The swollen bottom or
ovary contains one or more ovules where the female
gametophyte is found. The ovary connects to a slender
structure called the style. At the top of style is the stigma
where the pollen lands. A flower may have multiple carples
or only one.
A flower can have both male and female reproductive organs.
If it does, it is termed perfect but if it does not it is termed
imperfect. Male flowers are called staminate flowers and
female flowers are called carpellate flowers. If both flowers
are on the same plant, then the plant is said to be
monoecious but if they are on different plants (male date
palms vs. female date palms), then the plant is dioecious.
Corn is a monoecious plant with stamenate and carpellate
flowers on the same plant. Sagittaria is dioecious. The plant
on left is male and the right female.
Which of the following is not found on
a flower?
A) sepals
B) petals
C) Plasmodesmata
D) Stamen
E) carpels
ANS: C
The four parts to a flower are the
petals, sepals, stamen, and carpels.
The plasmodesmata are pores between
adjacent plant cells.
Microgametogenesis-In the anther chambers there are
microspore mother cells (2n). They undergo meiosis to
produce 4 microspores (n). The microspores undergoes
mitosis to produce a spore with two nuclei, one becomes
the tube cell and the other the generative cell. The
generative cell will undergo mitosis once more to make two
sperm nuclei. This is the male gametophyte. The male
gametophyte will form a very drought resistant pollen grain.
The shape is species specific.
Pollen gives rise to
A) male gametophyte
B) Microspores
C) Eggs
D) sporophytes
ANS: A
Pollen gives rise to the male
gametophyte which has three cells.
Megagametogenesis-Is the formation of the female
gametophyte. Inside the ovary, there is one or more ovules.
Each ovule has a megaspore mother cell (2n). This cell will
undergo meiosis to produce 4 megaspores (n). Three of cells
will degenerate but one will survive to give rise to female
gametophyte. The megaspore (n) will under-go three mitotic
divisions without cytokinesis to give rise to eight nuclei.
Division of the cytoplasm will then occur. It will produce
seven cells. Three on each end and one in the middle.
The one in the middle will have two distinct nuclei
(n+n). On the top are three antipodal cells. These
will degenerate. At the bottom, there is a central
cell which is the egg cell (n). It is flanked by two
living cells called syngerids.
Pollination and fertilizationOnce a pollen falls on the stigma of the carpel, the pollen
begins to digest the neck of the style and sending down a
pollen tube. This pollen tube will have the tube nucleus in it.
It will be followed by the generative nucleus which will
undergo mitosis to form 2 sperm nuclei. The pollen tube is
making its way to ovule which is housing the female
gametophyte. There is an opening in the ovule called the
micropylle. The pollen tube sends one sperm nucleus to
fertilize the egg, and the second to fertilize the polar nuclei or
large central cell. This cell becomes triploid (3n) and is called
endosperm.
The structure above is
A) a pollen grain
B) a sporophyte
C) Megaphyll
D) female gametophyte
ANS: D
The female gametophyte in the
alternation of generations will produce
an egg cell. In angiosperms, the
female gametophyte is 7 cells large.
This is a case of double fertilization. The fertilized egg or
zygote will give rise to the seed embyro, the endosperm will
provide nutrients to the embryo. The ovule will become the
seed coat. The ovary under the influence of hormomes will
become the fruit of the plant. The fruit or pericarp of the
plant is used to protect enclosed seeds and aids in their
dispersal.
In angiosperms, double fertilization
occurs. What cells are fertilized?
A) antipodal cell and the central cell
B) egg cell and the central cell
C) egg cell and a synergid
D) antipodal cells and a synergid
ANS: B
The egg cell and the central cell. The
egg cell will give rise to the plant
embryo and the central cell will give
rise to the endosperm.
Different types of fruit
and seed. Fruit is
used to protect the
seed and entice
animals to eat to carry
the seed to another
location.
The egg cell and the central cell are both
fertilized, what do they give rise to?
A) The egg cell makes the embryo and the
central cell make triploid endosperm.
C) The egg cell makes the sporophyte and
the central cell make gametophyte.
B) The egg cell makes the fruit and the
central cell make flower.
D) The egg cell makes the flower and the
central cell make diploid endosperm.
ANS: A
The egg cell makes the embryo and the
central cell make triploid endosperm
These are the major groups of flowering plants. The two
major ones are the monocots and eudicots (formerly dicots)
Comparison of monocots versus dicots.
A plant had been observed and it has
parallel veins, three carpels, six stamen
and a fibrous root system. What is the
best classification of this plant?
A) gymnosperm that is a monocot
B) gymnosperm that is a dicot
C) angiosperm that is a monocot
D) angiosperm that is a dicot
ANS:
C
There are four groups of angiosperms but
the majority fall into two categoriesmonocots and dicots. Monocots have
parallel veins while dicots have branched
veins. Monocots have floral parts in threes
and multiples of three while dicots have
floral parts in fours or fives and multiples
of fours or fives. Monocots have a fibrous
root system while dicots have one main root
with branching roots coming off.