Let’s first look at the autogenous hypothesis: Specialized internal membranes that derived from a procaryotic plasma membrane evolved into organelles characteristic of euchariotic cells. The nuclear envelope, endoplasmic reticulum, Golgi complex and organelles bounded by single membranes evolved this way.
Don’t you see a problem with this hypothesis? A very rudimentary, basic structure (plasmamembrane) turns into a highly complex structure, then differentiates into unique, specialized organelles. This is contrary to nature and cannot be demonstrated.
Now
for the endosymbiotic hypothesis: This
seems to be Cantleave’s first choice. This hypothesis proposes that forerunners
of eucaryotic cells were associations of small, symbiotic procaryotic cells
living within larger procaryotic cells. The focus here is mainly on the origin
of chloroplasts and mitochondria. Chloroplasts are believed to be descendants
of photosynthetic procaryotes. The proposed ancestors of mitochondria are
believed to have been oxygen-requiring heterotrophic bacteria (heterotrophs
obtain food by eating other organisms or their byproducts). It has been
suggested that photosynthetic procaryotes and oxygen-requiring heterotrophs
gained entry into the large procaryotic cell as undigested prey or internal
parasites.
In the case of invagination of food, it would be stored as an inclusion or it would by broken down by enzymes. The organism is not normally assimilated into the predatory cell. What about the notion of internal parasites? These do not get assimilated into the host either. They live off the host but does not become part of the host.
Some questions: 1) How did these get past the capsule, cell wall and cytoplasmic membrane? 2) How did they survive inside the host long enough for them to be assimilated by the host? Again this is contrary to nature. 3) We cannot demonstrate the process in a lab in favourable conditions. What are the chances of this process taking place in unfavorable conditions outside?
Cantleave
poses the question: Why would two systems of reproduction occur within a single
cell unless these organelles have a different ancestry from the nucleus? Your answer is: Different organisms were assimilated into a single organism. I
answer, because they were designed that way.
