Lecture #10- Living Gymnosperms II: Conifers Flashcards
What are Conifers?
Cone bearing
How do most conifers produce seeds
The seeds are produced in cones composed of overlapping scales (which are modified leaves)
-few produce fleshy false fruit
What kind of wood do conifers have?
Resinous wood
-NONE have vessels
Why are the seeds naked?
Weeds arent wrapped in anything,
- they ae produced in the integument (aka the false fleshy fruit)
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What is the function of resin?
Protective function
Reproduction of Conifers?
Pollen drawn into pollen chamber
Pollin germinates to form a pollen tube which grows to the egg of one of possibly 3 archegonium
Whats different with the reproduction of Pinus?
The fusion of male and female gametes can be delayed for a year or more after pollination
What does it mean to have 3 Generations?
Seed coat (integument) is of the parent generation(2n). In the integument is the megagametophyte generation (female n). Tissue surrounding the embryo (offspring2n) -seed coat, megagametophyte, embryo
What is the endosperm/food reserves for?
for then the seed gets released, it gives it a better chance of producing a full on tree
Characteristics of the Family Pinaceae
- Ecto
- monoecious
- needles for leaves in bundles
- woody cones: 2 ovule per scale, 3-18 cotyledons
- mom and dad are on the same tree as separate cones
How many needles are in the bundles of hardwood pines?
2 or 3 needles per bundles
How many needles are in the bundles of softwood pines?
5 needles per bundle
Characteristics of the Family Cupressaceae?
- Endo
- Mono or dioecious
- scale like leaves
- woody ovulate cones; scales fused
- 2 ovules per scale and 2 cptyledons
Why are Junipers special?
They have a berry instead of cones
- the cone scale became fleshy
- we use the berries to flavour gin
Characteristics of the Family Araucaruaceae?
- Endo
- Mono or dioecious
- needle like leaves
- ovulate cones; scales fused
- 1 ovule per scale and 2 cotyledons
- Gondwana family (evolved after the breakup)
