Genus Pinus .
Seed is born
on the cone
"Conifers" - produce cones
Leaves - needles bundle of 3 is
called a fascicle.
Male cones are 2N. Other names for
male cone are:
Microstrobilus
Pollen cone
Staminate
cone
They develop in the spring
Male
Cone
Class Gymnospermae
Subdivision Pteropsida
Division
Tracheophyta
Kingdom Plantae
The female cone:
Other
names include: Megastrobilus, Carpellate cone, Ovulate
cone
There are three types of cones: a 1st year, 2nd year, and 3rd
year.
The 1st year female cone has a protective layer between the pollen
(male) grain and the egg, which is called the nucellus.
Germination occurs when the pollen tube pierces the nucellus in order for the
pollen to get to the egg, which now is fertilization.
The 2nd year female
cone is completely closed. The carpells close trapping the sperm pollen inside
where it is becoming a zygote to form a seed.
The 3rd year female cone opens
up to release the seeds.
Female
Cone 1st year (Pollination cone)
Class Gymnospermae
Subdivision Pteropsida
Division
Tracheophyta
Kingdom Plantae
Female
Cone 2nd year (Fertilization cone)
Class Gymnospermae
Subdivision Pteropsida
Division
Tracheophyta
Kingdom Plantae
Female
Cone 3rd year (Seed cone)
Class Gymnospermae
Subdivision Pteropsida
Division
Tracheophyta
Kingdom Plantae
Class Angiospermae
Characteristics:
-Covered
seed
-Seeds are covered by the flower or a fruit
-No archegonium
present
-Germination is long
-Double fertilization (3N)
structure
Study page 154 parts of the mature
seed.
There are four sets of floral organs:
1. Sepals, collectively called Calyx.
2. Petals, collectively
called Corolla.
*3. Stamen,
male reproductive organ with two parts known as the Anther and
Filament.
*4. Pistil, female reproductive
organ with three parts called the Stigma, Style, and
Ovary.
*Are necessary for reproduction to occur.
Male anthers
produce pollen. Occurs in self pollenation.
Pollen is setting on top of the
stigma awaiting for the female to accept it.
Angiosperm
Female Gametophyte Development
An 8 nucleated stage occurs. See the
last phase pictures for labeled parts.
What
is happening:
1. The two polar nuclei will fuse together to form the fusion
nucleus (2N).
2. Sperm #1 (1N) fertilizes the fusion nucleus (2N) to form the
Primary Endosperm Nucleus (3N).
3. Sperm #2 (1N) will fertilize the egg to
form a zygote 2N.
This
phase of floral morphology shows the pollen tube as the male pollen passes the
inner and outer integuments (not labeled but see pg 155 pictures) to get to the
egg and the polar nuclei for fertilization within the flower.
A
model of a flower with some parts that you need to familiarize yourself with for
the practical. Petals are collectively called
the corolla. Sepals
are collectively called the calyx.
Another
model that you need to be familiar with for the lab
practical.
Characteristics of Dicots:
1. They have a woody stem
2. They have multiples of 4 or 5 flower
parts
3. They have palmately veins
4. One large vascular
bundle
Click each link to see individual parts of this model
labeled with function.
Parts:
Parenchyma (for food storage)
Collenchyma
(support)
Sclerenchyma (support and protection)
Chlorenchyma
(chlorophyll)
Xylem (transport water)
Phloem (transport food)
Vascular
Cambium (secretes a ring of xylem each year (only in dicots)
Epidermis (outer
most layer for protection)
Characteristics
of Monocots:
1. They have a herbaceous (leafy or green)
stem
2. They have 3 or multiples of 3 flower parts
3. They have parallel
veins
4. Many scattered vascular bundles (xylem &
phloem)
Click each link to see individual parts of this model
labeled with function.
Parts:
Parenchyma (for food storage)
Collenchyma
(support)
Sclerenchyma (support and protection)
Chlorenchyma
(chlorophyll)
Xylem (transport water)
Phloem (transport food)
Epidermis
(outer most layer for protection)
Study pages 154 & 155 in your lab
manual.
In this model of the root, know where this part
is located: Meristematic (mitosis/growth)
August 6, 2001
Contact Dr. Billy Williams at BWilliams@dscc.edu.
Photography by Jonathon Mooney.
