Oleander (Nerium oleander)

Crank Up The Funky Music, This is Reproduction!

Although established Nerium oleander is considered to be a very drought resistant plant, it prefers to live in a very moist habitat because in its early stages of life there is a greater need for water then in the adult stages.  Oleander engages in sexual reproduction, however it can self pollinate, but this of course is not ideal because genetic diversity is very important in order to survive as a species. 
Photo of a bee polinating a flower on Oleander thanks to B÷hringer FriedrichOleander flower thanks to A. Barra
When Nerium oleander is engaging in sexual reproduction it goes through the process of gametic meiosis.  At the beginning of this cycle there is a multicellular diploid sporophyte that produces haploid spores via meiosis.  From these spores, multicellular, haploid gametophytes, via mitosis, arise.  These then produce haploid gametes, often referred to as egg and sperm, via mitosis.  These then fertilize and produce a diploid zygote.  This zygote, often referred to as a seed, then goes through mitosis to produce another multicellular, diploid sporophyte, starting the cycle all over. 
Oleander seeds thanks to J˙lio ReisGametic meiosis thanks to Menchi
Nerium oleander, like all flowering plants, goes through double fertilization.  This process starts when the pollen grain lands on the stigma of a plant.  It then creates a pollen tube that goes down through the style to the ovary of the plant.  Once it has reached the ovary two sperm are released.  One fuses with the egg to create the diploid zygote.  The other fuses with the multiple nuclei to create the endosperm.  This endosperm is the nutrient rich part of the seed that the early zygote uses to germinate and grow before it photosynthesizes for itself.
Pollen tube going down to ovary thanks to E. Strasburger United States Public DomainOleander flowers thanks to Vasile Coardos

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