GYMNOSPERMS
What are megasporophylls
A leaf where megaspores form
What are bracts?
A small flap beneath the ovuliferous scale
Gymnosperms do not need water for fertilization because they have?
Air borne pollen
What can we see inside the megagametophyte>
Archegonium adn egg that is housed in the archegonium
Why are gymnosperms considered naked?
Because their ovules are not enclosed by a carpel layer
What are the general characteristics of the pine seed?
Contains the embryo Protects the embryo Provides food at crucial periods of establishment
What is an endodermis
Controls the amount of water that is transported to the inner part of the plant
Which have more naked ovules, cycads or pines?
Cycads
Are cycads dioecious or monoecious
Cycads are dioecious and produces pollen and seed cones
Which have more naked seeds zamia or cycas?
Cycas
This type of cycad have megasporophylls that aren't grouped into cones
Cycas circinalis
This cycas plant is used to make sago
Cycas revoluta - oliva/ sago plam
If gingkos aren't evergreen then what are they?
Deciduoud
Gymnosperm seeds are not that susceptible to?
Dessication
Is the megasporangium haploid or diploid?
Diploid
Pine leaves have...
Endodermis and transfusion tissue
What are megaphylls?
Euphylls (they have leaf gaps)
What type of arrangement do pine roots exhibit?
Exarch arrangement
Ovulare cones are?
Female cones; seed cones
These trees dominated the land before
Fern trees
Most gymnosperms are evergreen except for?
Gingkos
What are the advantages of symbiote cyanobacteria
Give the plant a higher capability to get nutrients and produce certain metabolites that are unique to cycads
Gymnosperm etymology
Gymno = naked; sperm = seed
What are the advantages of narrow leaves?
Help conserve water?
Megasporangium has a ___ covering
Integument
Why did fern trees go extinct?
Lack of seeds and secondary growth
What are ovuliferous scales?
Large woody leaves that form the female cone of conifers and related trees
What are transfusion tissue?
Layer of thin walled cells found between the endodermis and the vascular tissues and facilitates the transfer of materials between the ordinary vascular tissue and tissues outside the endodermis
What shape do pine leaves have?
Linear to acicular (needle-shaped)
What are albuminous cells?
Load and unload sugar into the cavity of sieve cells
Describe the tracheids and rays of cycads
Long and wide tracheids with massive rays
Gymnosperms may either have what types of leaves?
Long shoots with papery leaves, short shoots with long needle like leaves
Pollen is part of what reproductive part of gymnosperms
Male
Explain dioecious gymnosperms
Male and female cones in separate plants
Staminate cones are?
Male cones; pollen cones
Within the megasporangium we could find the
Megagametophyte (n)
All gymnosperm leaves including the needle like leaves of conifers are considered to be?
Megaphylls
What is the pine ovule?
Megaspore mother cell/ megasporocyte plus the integument
What can we see in cycas seed cones
Megasporophylls and seed cones
The developing seeds of gymnosperms are often covered by what?
Megasporophylls of ovuliferous scales
Ovuliferous scales are also called?
Megasprophylls
Pollen entrance for ferilization
Micropyle
What part of the Cycas revoluta is used to make palm
Middle of the trunk
Gymnosperm leaves look like?
Monocot leaves
All gymnosperms have no side branches which means they are?
Monopodial
What is the meaning of gymnosperm?
Naked seed
Do pine leaves store water?
No
Is there a division between the spongy and palisade parenchyma
No
Do seeds detriorate easily? Why is this important?
No, for seed dispersal
Do gymnosperms shed their leaves?
No, leaves remain attached to the plant even during winter
Do cycads form trees?
No, only shrubs
What type of wood do gymnosperms have?
Non porous wood
The phloem of gymnosperms are composed of what?
Only sieve cells as they lack sieve tube members. They also have albuminous cells
The xylem of gymnosperms are composed of what?
Only tracheids as they lack vessel elements
What is an ovule?
Organ that forms seeds of the flowering plant
What is a carpel layer?
Outer layers of the ovule that develop into a seed coat
These are the longest living and tallest tree species
Pines
What are the general characteristics of pollen
Pollen distributes sperm through the wind Pollen tube grows to egg Winged pollen with air bladders Pollen tube is the passageway of sperm to the ovule
Gymnosperm xylem rays are almost exclusively uniseriate except when they bear?
Resin canals
These are root structures that are prominent in gymnosperms (pine specifically)
Resin canals, sclerotic cells, crushed primary phloem
Conifers are covered by?
Resins
Pollen grains ___ with 2 air bladders
Saccate
Seeds are produced on an open...
Scale
What are gymnosperms?
Seed plants without flowers
Gymnosperms are evolved to have?
Seeds without flowers
Explain monoecious gymnosperms
Separate male and female cones in the same plant
Describe cycads
Short plants, stems are similar to seed ferns
What are fascicles?
Short shoot with stem tissue and needle like leaves?
What type of leaf venation do gymnosperms have?
Simple leaf venation
Are gymnosperms hard or soft wood?
Soft wood
Which generation is more dominant: sporophyte or gametophyte generation?
Sporophyte generation
These can be found in the leaves in some gymnosperm species?
Sunken stomata and hyppodermis
These bacteria are found in the roots of cycads
Symbiote cyanobacteria
The lack of division of the spongy and palisade parenchyma is what type of character?
Synapomorphic
Conifers are adapted to what types of regions?
Temperate - cold
Where do gymnosperms usually live?
Temperate regions
Pine leaves protects?
The leaf/ tree from too much water (Reduces environmental pressure; allows them to survive harsh winters and doesn't require them to shed of their leaves)
Why are primary phloem crushed?
They get crushed due to the continued accumulation of the secondary xylem
Why are gymnosperms said to be more advanced than spores?
They have seeds
Why are they considered soft wood
They lack vessel elements, fibers, and axial parenchyma cells.
Broad, regular, tropical leaves are susceptible too?
Too much environmental pressure (temperature is too much of a pressure)
Land plants are also known as
Tracheophytes
Gymnosperm transfusion tissue consists of?
Transfusion parenchyma and transfusion tracheids (more or less cubodial with circular bordered pits)
Where can sterile bracts be found?
Underneath the ovuliferous scale
In gymnosperms, xylem rays are almost exclusively...
Uniseriate
Where are endodermis usually found in gymnosperms?
Usually in roots but also in leaves
What happens if pine leaves get wet or accumulate snow?
Water adn snow just flows to the tip
When can gymnosperms have branches?
When they are made that way to be bonsai
Are cycads ornamentals?
Yes
Can resin ducts be also found in gymnosperm leaves?
Yes but they are reduced
How many microsporangia do each scale or sporophyll of male cones have?
2
How many seeds to each ovuliferous scale or megasporophyll have?
2 inverted winged seeds
How many leaves do fascicles have?
2-5
Seeds should be dessicated to how many percent in order for it to undergo dormancy/ resting stage
20%
How many cycad genera and species are there
9-10 genera 100 species
What are resin canals?
- PRotects the plant from fires, predators, and sickness - Resin can preserve animals through amber
What are sclerotic cells?
- Part of the outer layer of the root. - They function as support, food conduction, water protection, and help deter excess water loss
What are the 7 conifer groups?
- Pines - Firs - Hemlocks - Junipers - Spruces - Yews (long-life span) - Red woods (long-life span)
What are the general characteristics of pollen cones
- Smaller bracts (in some) - Relatively smaller (miniature seed cone) - Usually found at the tips of branches - usually yellow
Is the integument haploid or diploid
(diploid)