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flowers and cones reproduction
Reproduction With Cones and Flowers

Alternation of Generations
Life Cycle of Gymnosperms
Structure of Flowers
Life Cycle of Angiosperms
Pollination
Fertilization in Angiosperms

Alternation of Generations
Gametophytes~inside plants, produces male and female gametes
Sporophyte~the plant itself
Gametophyte becomes a sporophyte then uses gametophyte to make another sporophyte

Life Cycle of Gymnosperms
Gametophytes~pollencone(male)& seedcone(female)
The pollination process for Gymnosperms usually take about 2years
Pollin travels by wind and lands on female cones to start reproduction

Structure of Flowers
Gametophytes are on the same flower usually but some are on the same plant
Sepals and Petals are parts of the flower that has no part of reproduction so they may also be called sterile leaves.
Stamen and Carpel are the gametophytes of flowers
Gametophyte~stamen(male)& carpel(female)

Life Cycle of Angiosperms
Gametophytes~embryo sac(female)& pollen(male)

Pollination
Gymnosperms and Angiosperms are pollinated differently
Angiosperms are mostly pollinated by animals but some may also be pollinated by wind
Gymnosperms are mostly pollinated by wind

Fertilization in Angiosperms
Double Fertilzation occurs in Angiosperms
1. Sperm + Eggs = Zygote (to produce a sporophyte)
2. Sperm + Polar Nuclei = Endosperm (to give nutrients to the embryo)
Angiosperms have been really successful with fertilization and it is possible that double fertilization is the reason why it has been successful
Angiosperms only make the endosperm to get food only if the egg is fertilized and Gymnosperms usually get food before fertilization so if the egg is not fertilized the food goes to waste


 

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