1. Conifers
2 kinds of cones

2. Male vs. Female Cones
Male
Pollen cones
Female
Seed cones
immature

3. Male
Female
immature

4. Mature Immature

5. “Naked” and “Covered”

6. Reproduction
Scales
Male cones produce male gametophytes called pollen grain
Female cones (seed cone) produce female gametophytes called ovules (eggs)
Embryo – same idea as zygote (egg+sperm)

7. In this example we are using a pine cone
Conifer Reproduction
In this example we are using a pine cone
seed coat
Egg
(n)
Unfertilized ovule
Female
gametophyte
(n)

8. Unfertilized
ovule

9. Conifer Reproduction Female gametophyte (n) Micropyle
Fertilization initiates the transformation of the ovule into a seed
Female
gametophyte (n)
Discharged
sperm nucleus (n)
Micropyle
Male gametophyte
(pollen grain)
(n)

10. Conifer Reproduction Seed coat Food supply
Compared to a single-celled spore, a seed is much more resistant and complex
Seed coat
Food supply
Embryo (2n)
Inside the seed
(new sporophyte)

11. Rise to the Angiosperms
Seed plants appeared ~360 mya
with the rise of the Gymnosperms
Flowering plants (Angiosperms)
– the other surviving lineage – appeared ~200 million years later