Guru
Guru
Those reading... Yea, I guess this is me not know what I am talking about yet again as I make rs199 FAIL complete!!
I told the poster to research... of course they never do and then... I have to blast them.
Guru
And to finish off the complete FAIL...
http://www.ncbi.nlm.nih.gov/books/NBK28332/
The simplest way of achieving this is for daughter cells to remain together after each cell division. Even some procaryotic cells show such social behavior in a primitive form. Myxobacteria, for example, live in the soil and feed on insoluble organic molecules that they break down by secreting degradative enzymes. They stay together in loose colonies in which the digestive enzymes secreted by individual cells are pooled, thus increasing the efficiency of feeding (the "wolf-pack" effect). These cells indeed represent a peak of social sophistication among procaryotes, for when food supplies are exhausted, the cells aggregate tightly together and form a multicellular fruiting body (Figure 1-31), within which the bacteria differentiate into spores that can survive even in extremely hostile conditions. When conditions are more favorable, the spores in a fruiting body germinate to produce a new swarm of bacteria.
or this
Green algae (not to be confused with the procaryotic "blue-green algae" or cyanobacteria) are eucaryotes that exist as unicellular, colonial, or multicellular forms (Figure 1-32). Different species of green algae can be arranged in order of complexity, illustrating the kind of progression that probably occurred in the evolution of higher plants and animals. Unicellular green algae, such as Chlamydomonas, resemble flagellated protozoa except that they possess chloroplasts, which enable them to carry out photosynthesis. In closely related genera, groups of flagellated cells live in colonies held together by a matrix of extracellular molecules secreted by the cells themselves. The simplest species (those of the genus Gonium) have the form of a concave disc made of 4, 8, 16, or 32 cells. Their flagella beat independently, but since they are all oriented in the same direction, they are able to propel the colony through the water. Each cell is equivalent to every other, and each can divide to give rise to an entirely new colony. Larger colonies are found in other genera, the most spectacular being Volvox, some of whose species have as many as 50,000 or more cells linked together to form a hollow sphere. In Volvox the individual cells forming a colony are connected by fine cytoplasmic bridges so that the beating of their flagella is coordinated to propel the entire colony along like a rolling ball (see Figure 1-32). Within the Volvox colony there is some division of labor among cells, with a small number of cells being specialized for reproduction and serving as precursors of new colonies. The other cells are so dependent on one another that they cannot live in isolation, and the organism dies if the colony is disrupted.
Last edited by DBM aka FDS; Jan 31 2012 at 12:02 PM.
Guru
http://en.wikipedia.org/wiki/Volvox
Volvox... been around for 200 million years, that's a long time without evolving now isn't it... Maybe it will evolve next week huh?!?!
Guru
FAIL!!!!
I told you to look stuff up, why did you not look it up? Please look things up next time please...
Guru
I sent you this and you refused to read it... It's all right there... all of it...
Did you read?Originally Posted by DBM aka FDS
Guru
There ya go again, using the word colony.
Multicellular Life Evolves in Laboratory
No where in the article does it state: 'colony of yeast replicate multicellular life' <--- Just more red herrings from you.An evolutionary transition that took several billion years to occur in nature has happened in a laboratory, and it needed just 60 days.
Under artificial pressure to become larger, single-celled yeast became multicellular creatures. That crucial step is responsible for life’s progression beyond algae and bacteria, and while the latest work doesn’t duplicate prehistoric transitions, it could help reveal the principles guiding them.
“This is actually simple. It doesn’t need mystical complexity or a lot of the things that people have hypothesized — special genes, a huge genome, very unnatural conditions,” said evolutionary biologist Michael Travisano of the University of Minnesota, co-author of a study Jan. 17 in the Proceedings of the National Academy of Sciences.
In the new study, researchers led by Travisano and William Ratcliff grew brewer’s yeast, a common single-celled organism, in flasks of nutrient-rich broth.
Once per day they shook the flasks, removed yeast that most rapidly settled to the bottom, and used it to start new cultures. Free-floating yeast were left behind, while yeast that gathered in heavy, fast-falling clumps survived to reproduce.
Within just a few weeks, individual yeast cells still retained their singular identities, but clumped together easily. At the end of two months, the clumps were a permanent arrangement. Each strain had evolved to be truly multicellular, displaying all the tendencies associated with “higher” forms of life: a division of labor between specialized cells, juvenile and adult life stages, and multicellular offspring.
“Multicellularity is the ultimate in cooperation,” said Travisano, who wants to understand how cooperation emerges in selfishly competing organisms. “Multiple cells make make up an individual that cooperates for the benefit of the whole. Sometimes cells give up their ability to reproduce for the benefit of close kin.”
Since the late 1990s, experimental evolution studies have attempted to induce multicellularity in laboratory settings. While some fascinating entities have evolved — Richard Lenski’s kaleidoscopically adapting E. coli, Paul Rainey’s visible-to-the-naked-eye bacterial biofilms — true multicellularity remained elusive.
According to Travisano, too much emphasis was placed on identifying some genetic essence of complexity. The new study suggests that environmental conditions are paramount: Give single-celled organisms reason to go multicellular, and they will.
Apart from insights into complexity’s origins, the findings could have implications for researchers in other fields. While multicellularity would have a hard time emerging now in nature, where existing animals have a competitive advantage, the underlying lesson of rapid, radical evolution is universal.
“That idea of easy transformability changes your perspective,” said Travisano. “I’m certain that rapid evolution occurs. We just don’t know to look for it.”
Targeted breeding of single-celled organisms into complex, multicellular forms could also become a biotechnological production technique.
“If you want to have some organism that makes ethanol or a novel compound, then — apart from using genetic engineering — you could do selection experiments” to shape their evolution, Travisano said. “What we’re doing right here, engineering via artificial selection, is something we’ve done for centuries with animals and agriculture.”
Also, once again; you will not answer this question:
If the single cell yeast did not become multicellular via Evolution, then why is there multicellular offspring?
Last edited by rstones199; Jan 31 2012 at 12:33 PM.
rstones199 - The Voice Of Reason!
When you say 'god', which one are you referring to?
I'm not saying let's kill all the stupid people, I'm just saying let's remove all the warning labels and let the problem sort itself out.
Guru
In your propaganda of course it isn't... That is why you getting your links from places like Wired...
Also, I said that it didn't replicate multicellular life. That's just retarded. If you think so - post something - ANYTHING where it states, outside of propaganda sites, that yeast replicates multicellular life. BECAUSE THAT IS IMPOSSIBLE!!!
Guru
Uh-huh:
Whats the next red herring?Within just a few weeks, individual yeast cells still retained their singular identities, but clumped together easily. At the end of two months, the clumps were a permanent arrangement. Each strain had evolved to be truly multicellular, displaying all the tendencies associated with “higher” forms of life: a division of labor between specialized cells, juvenile and adult life stages, and multicellular offspring.
rstones199 - The Voice Of Reason!
When you say 'god', which one are you referring to?
I'm not saying let's kill all the stupid people, I'm just saying let's remove all the warning labels and let the problem sort itself out.
Guru
There I go again with the Colony...
Funny...
http://www.ncbi.nlm.nih.gov/pubmed/10806103
Yeast colonies synchronise their growth and development.Palková Z, Forstová J.
SourceDepartment of Genetics and Microbiology, Charles University, Vinicná 5, Czech Republic. zdenap@prfdec.natur.cuni.cz.
Abstract
The ability to emit and receive signals over long distances is one of the characteristic attributes of multicellular organisms. Such communication can be mediated in different manners (by chemical compounds, light waves, acoustic waves etc.) and usually is reflected in the behaviour of the communicating organisms. Recently, we reported that individual yeast colonies, organised multicellular structures, can also communicate at long distance by means of volatile ammonia, which is produced by colonies in pulses separated by acidification of the medium. Here, we demonstrate that the colony that first reached the stage of intense ammonia production induces ammonia production response in surrounding colonies regardless of their age, causing the synchronisation of their NH(3) pulses and, consequently, the mutual affection of their growth. Also an artificial source of ammonia (but neither NH(4)(+) nor NaOH gradients) can immediately induce the ammonia production even in the colony starting its acidic stage of the development. The repeated transition of Candida mogii colonies from the acidic phase to the phase of intensive ammonia production is accompanied by dramatic changes in colony morphology and also in cell morphology and growth. Relatively smooth colonies in the acidic phase are formed by growing pseudohyphae. After ammonia induction, pseudohyphae decompose into non-dividing yeast-like cells, which rearrange themselves into ruffled spaghetti-like structures. The synchronisation of colony growth, that also exists between yeast colonies of different genera, could be important in establishing their optimal distribution in a natural habitat.
PMID: 10806103 [PubMed - indexed for MEDLINE] Free full text
What that site is: The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information.
Here is the whole paper: http://jcs.biologists.org/content/113/11/1923.full.pdf
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