Human Anatomy, Physiology, and Medicine. Anything human!
Okay, I will follow the apical complex.
Can we follow this through in some kind of deductible manner? or is that not the proper way.
First a definition:
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Classes & subclasses
Apicomplexa is a phylum in the kingdom Protista. The Apicomplexa are a large group of protozoa characterized by the presence of an apical complex at some point in their life-cycle. They are exclusively parasitic and completely lack flagella or pseudopods except for certain gamete stages. Diseases caused by Apicomplexa include:
Toxoplasmosis (Toxoplasma gondii)
Most members have a complex life-cycle, involving both asexual and sexual reproduction. Typically, a host is infected by ingesting cysts, which divide to produce sporozoites that enter its cells. Eventually, the cells burst, releasing merozoites which infect new cells. This may occur several times, until gamonts are produced, forming gametes that fuse to create new cysts. There are many variations on this basic pattern, however, and many Apicomplexa have more than one host.
The apical complex includes vesicles called rhoptries and micronemes, which open at the anterior of the cell. These secrete enzymes that allow the parasite to enter other cells. The tip is surrounded by a band of microtubules, called the polar ring, and among the Conoidasida there is also a funnel of rods called the conoid. Over the rest of the cell, except for a diminished mouth called the micropore, the membrane is supported by vesicles called alveoli, forming a semi-rigid pellicle.
The presence of alveoli and other traits place the Apicomplexa among a group called the alveolates. Several related flagellates, such as Perkinsus and Colpodella have structures similar to the polar ring and were formerly included here, but most appear to be closer relatives of the dinoflagellates. They are probably similar to the common ancestor of the two groups.
Another similarity is that apicomplexan cells contain a single plastid, called the apicoplast, surrounded by either 3 or four membranes. Its functions are thought to include tasks such as lipid synthesis, it appears to be necessary for survival. They are generally considered to share a common origin with the chloroplasts of dinoflagellates, although some studies suggest they are ultimately derived from green rather than red algae.
The Apicomplexa comprise the bulk of what used to be called the Sporozoa, a group for parasitic protozoans without flagella, pseudopods, or cilia. Most of the Apicomplexa are motile however. The other main lines were the Ascetosporea, the Myxozoa (now known to be derived from animals), and the Microsporidia (now known to be derived from fungi). Sometimes the name Sporozoa is taken as a synonym for the Apicomplexa, or occasionally as a subset.
Retrieved from "http://en.wikipedia.org/wiki/Apicomplexa"
Tam Tam a lot of references here, but, is this considered a natural phenomenon? or is this part of the construct?
Will look more into this because a lot of infomation seems to indicated here, about, the way protists are formed. Is very interesting.
rhoptries and micronemes from above definitions:
Here is reference to toxoplasma
http://www.mbl.edu/mpm/mpm-2002/abstrac ... hp?id=205B
t.gondii and protein fusions:
This on host cell invasion:
http://parasitology.informatik.uni-wuer ... /0673.html
This is loaded with information on just this apical complex.
Skytoll, I wil forward those links to you later this evening...(re: yesterday)
Evolution of sex and recombination: theory
http://www.indiana.edu/~curtweb/Researc ... heory.html
and also: Parasites.....
and the snail.......
http://links.jstor.org/sici?sici=0014-3 ... size=LARGE
I was trying to find combo of parasite/ seed, etc., and came across this article on birds and Trichomoniasis
http://list.uvm.edu/cgi-bin/wa?A2=ind04 ... =1&P=13792
and.....this is really interesting......
http://list.uvm.edu/cgi-bin/wa?A2=ind04 ... =1&P=13915
This is all I could find re: BWF; they desire: molecular approaches to studying fungi and pathenogens
oh wait a minute, are you talking about Blackwater Fever? hmm...
If so, that would be the Plasmodium.....i.e., Malaria
Still on parasites/ seeds.......:
Both Ascaris and Trichuris (roundworm) (whipworm) eggs are produced in abundance and are easy to identify when present in paleofeces. Enterobius (pinworm) eggs are not as abundant in paleofeces, and are known to occur in less than 5% of infected populations. Parasites that live in fish flesh, such as Diphyllobothrium (Dibothrycephalus), a tapeworm that infect humans when we eat raw or undercooked fish containing the parasite. These parasites live in fish in temperate regions. When we recovered then in paleofeces deposited in the Atacama Desert of Chile, our interpretation was that the people who passed through this area had been in the Altiplano eating fish from the lakes. The site that yielded the paleofeces was on a caravan route from the Altiplano to the coast or vice versa (Cummings, Nepstad-Thornberry, and Puseman 2000).
This is short and interesting on the Cloning of the Plasmodium:
http://www.nature.com/nature/journal/v4 ... 01107.html
Finally, an article on the Superweed.............
http://evolution.berkeley.edu/evolibrar ... _superweed
Gliding motility in cyanobacteria: observations and possible explanations
A1 Laboratory of Cell Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021-6399, USA
Abstract. Cyanobacteria are a morphologically diverse group of phototrophic prokaryotes that are capable of a peculiar type of motility characterized as gliding. Gliding motility requires contact with a solid surface and occurs in a direction parallel to the long axis of the cell or filament. Although the mechanistic basis for gliding motility in cyanobacteria has not been established, recent ultrastructural work has helped to identify characteristic structural features that may play a role in this type of locomotion. Among these features are the distinct cell surfaces formed by specifically arranged protein fibrils and organelle-like structures, which may be involved in the secretion of mucilage during locomotion. The possible role of these ultrastructural features, as well as consequences for understanding the molecular basis of gliding motility in cyanobacteria, are the topic of this review.
While looking for the flagella and gliding motility etc.
Well, I found out that prokaryotes are now bacteria.
The Theory's Origin
The Endosymbiotic Theory of Eukaryote Evolution (Symboitic Theory) was first proposed by former Boston University Biologist Lynn Margulis in her 1981 book "Symbiosis in Cell Evolution". For years the theory was rejected by mainstream biologists who also considered Margulis to be an embarrasement to the field of biology. However, as both time and Margulis persisted, the theory is now mainstream science and is considered to explain the single most important event of the organic world.
What Is The Symbiotic Theory?
The Symbotic Theory provides an explanation for the evolution of multicelled organisms known as Eukaryotes from its ancestral forms of Prokaryotes. The theory states that these organisms evolved not by random genetic mutation as previously believed, but by a number of cell combinations. The simpler, less complex Prokaryotic derivitives combined or merged together into a single host cell to the extent of being an inseperable structure and formed today's multicellular Prokaryotes.
SOURCE: http://www.gpc.edu/~pgore/students/w96/ ... /intro.htm
BACTERIA r US........US r bacteria.....that is messed up!
The ICSP, formerly the International Committee on Systematic Bacteriology (ICSB), is the body that oversees the nomenclature of prokaryotes, determines the rules by which prokaryotes are named and whose Judicial Commission issues Opinions concerning taxonomic matters, revisions to the Bacteriological Code, etc. "
and......A JUDICIAL SYSTEM FOR OUR PROKARYOTES
"Officers of the International Committee on Systematics of Prokaryotes (ICSP) and of its Judicial Commission – 2005 to 2008".......
at SOURCE: http://www.the-icsp.org/
"The paradigm for evolution among prokaryotes has completely shifted. This shift was already becoming clear more than three years ago, according to a scholarly review article by three distinguished North American biologists, J. Peter Gogarten, W. Ford Doolittle and Jeffrey G. Lawrence. They began, "Accumulating prokaryotic gene and genome sequences reveal that the exchange of genetic information through both homology-dependent recombination and horizontal (lateral) gene transfer (HGT) is far more important, in quantity and quality, than hitherto imagined." Their supporting points include –
Gene transfer can create patterns of similarity and difference that mimic patterns produced by vertical descent. If taxa A and B successfully exchange genetic information (by homologous recombination or HGT) more frequently with each other than with taxon C, they will come to resemble each other more closely than they do C, both in gene content and gene sequence. Treelike patterns based on gene content or sequence will reflect these different frequencies, not some underlying organismal phylogeny.
HGT can fundamentally alter the character of a microbial species by introducing fully functional genes and gene clusters that can confer complex phenotypes and functions.
In contrast, variation introduced by point mutation will, most of the time, only adjust preexisting phenotypes.
While fitness peaks may never be explored if they must be reached one gene at a time, multiple genes may be acquired in the form of bacterial operons and gene clusters.
No gene appears immune to HGT. Genes encoding core metabolic functions..., conserved biosynthetic pathways..., components of the transcription and translation machinery..., and even ribosomal RNA... have been subject to HGT.
Ironically, ...preferential gene exchange could create many of the very same patterns of similarity and difference we usually attribute to vertical inheritance [see figure and legend at right]. Only a small subset of HGTs can be detected with confidence; the majority of transfers, especially those that occurred long ago or between closely related species, will likely escape detection. The mismatch repair genes themselves show a complex history of recombination attributed to loss and recovery (through horizontal transfer)....
Embracing gene transfer promises a broad and radical revision of the prokaryotic evolutionary paradigm.
HGT can occur between even very distantly related organisms, e.g., between bacteria and plants or fungi....
Of course natural selection will act as the arbiter of success for all recombinant cells.Today, we think the paradigm shift for evolution among prokaryotes needs more attention than it gets, because it challenges the strictly darwinian account of the source of new genetic programs. (What remaining evidence among prokaryotes supports that acccount?) Among eukaryotes also, the growing evidence for gene transfer is now shifting the evolutionary paradigm, and this shift also gets scant attention. Why?"
Soooooooo, by novel bacterias with added flagellas now we have prokaryotes.
Did these supreme intelligent scientists find a way to accelerate evolution? I wonder how they did that?
When did the amoeba grow a flagella?
Ah.........horizontal genes, just like that.
Do you know scientists that put things where they do not belong, really are lazy? Now, if they stopped to think that for every alteration there is a reaction? they might reconsider.
But, then that would put a wrench in the plan.
Well, so much for digging around for truth.
Cladistics it is. Captology makes us the protangonist, while cyanobacteria continues on it's merry way.
Well, we are the viruses aren't we? Symbiotic, horizontal gene transfer, rice/humans, plant/animal
Centaurs, here we come......or go.....
Last edited by Skytroll on Thu May 04, 2006 5:24 am, edited 1 time in total.
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