Evolution

[MC]

In a gene-centered view of evolution, life is regarded in terms of replicators—that is DNA molecules in the organism. In this paradigm, cells satisfy two fundamental conditions for the evolution of complexity. If freely-floating DNA molecules that code for enzymes are not enclosed in cells, the enzymes that benefit a given replicator (for example, by producing nucleotides) may do so less efficiently, and may in fact benefit competing replicators. If the entire DNA molecule of a replicator is enclosed in a cell, then the enzymes coded from the molecule will be kept close to the DNA molecule itself. The replicator will directly benefit from its encoded enzymes.

Biochemically, cell-like spheroids formed by proteinoids are observed by heating amino acids with phosphoric acid as a catalyst. They bear many of the basic features provided by cell membranes. Proteinoid-based protocells enclosing RNA molecules may have been the first cellular life forms on Earth. Some amphiphiles have the tendency to spontaneously form membranes in water. A spherically closed membrane contains water and is a hypothetical precursor to the modern cell membrane composed of proteins and phospholipid bilayer membranes.

Source: http://en.wikipedia.org/wiki/Cell_(biology)#Origin_of_the_first_cell

 

[VideoJinx]

"in the organism" ???:laff:


You really aren't saying much

 

[kam!]

edit;:::

keep in mind.. that all of our organs wouldn't just evolve at once, and also keep in mind that we need all these organs working at once to live..

In the evolution of vertebrates, a set of organs only has to evolve once. But you can go back even more.
e.g. smaller organism like cell colonies (the most likely precursor to complex life right now)
1 cell specialized for digestion is enough to become a whole digestive tract in a timeframe spanning 1 billion years.

Evolution doesn't work like "pop liver+kidney+stuff". In simpler organisms 1 specialized cell has the task a whole organ has in higher organisms.


Edit:
I guess this will be one of my last posts in this thread. I don't feel like reading the same post again, giving another source containing the same claims.
I don't feel like writing long posts to explain things that probably get ignored anyways (page 5?)

 

[VideoJinx]

LOL:laff:

Comon man <__<


if a cell was "specialized" for digest.. it would digest and excrete right???

can you point to where our intestines excretes waste into our blood?.. or does that not happen<__<

the specialized feature of it wouldve have to completely change...

I think this is as clean cut as it gets... evolution is a fraud =o

 

[MC]

VideoJinx, I have no idea what you're talking about.

 

[kam!]

LOL:laff:

Comon man <__<


if a cell was "specialized" for digest.. it would digest and excrete right???

can you point to where our intestines excretes waste into our blood?.. or does that not happen<__<

the specialized feature of it wouldve have to completely change...

I think this is as clean cut as it gets... evolution is a fraud =o

I'm getting a little fed up now and I'll resort to the "Jinx method":

LOL :laff:

http://ngm.nationalgeographic.com/ngm/0611/feature4/

(I really feel like you ignored my huge-ass long posts on the last page, and I want to save energy now since it's pointless to argue with you)

 

[DiebytheSword]

Jinx, you need to stop mocking their opinions just as much as I've asked them to stop mocking yours. Last freindly warning issued in this thread.

 

[Majin_You]

It's been a long time since I've studied Biology, but yes, single cells are capable of dividing.

Your memory is spot-on. Almost all somatic cells (which is to say, those cells that are not involved in the production of gametes) are capable of undergoing mitotic divisions, wherein the parent cell duplicates all macromolecules (DNA, RNA, proteins, etc.) and organelles, enlarges, and then splits off, portioning up the macromolecules, organelles, and cytoplasm into two, genetically identical (assuming there are no spontaneous mutations or defects in the proteins responsible for replicating the genome) daughter cells.

To make matters more complex, there's always the issue of distinguishing the eukaryotic cell (those that make up the protists, fungi, plants, and animals) from the prokaryotic cell (bacteria and some algae), as well as interactions between those cell types. An interesting method of evolution concerns the "development" of mitochondria (for plants and animals) and choloroplasts (for photosynthetic plants). Ostensibly, a proto-eukaryote ancenstor cell was infected by an intracellular bacterium, creating a symbiotic cell which provided structural and metabolic provisions for the parasitic bacterium, while the bacterium provided molecules such as ATP (ie: energy) for the host cell; after some concurrent replication of the host cell and bacterial parasite, the mitochondrion was, in essence, "born". The evidence that points to such a symbiotic relationship in the modern eukaryotic cell lies in the fact that the mitochondrion greatly resembles a typical, Gram-negative bacterium (not something that I really want to have to explain, as it might just make a boring post more boring; but if you really want to know about the Gram classification and Gram-staining, you can read about it here). The mitochondrion has two plasma membranes, a single, circular chromosome that comprises its genome, and 70S ribosomes (eukaryotes have larger, 80S ribosomes).

Such an advantageous relationship (gaining the ability to undergo aerobic respiration for a massive ATP payoff, while sacrificing a portion of the cellular volume for "rent") is believed to have led to the modern animal (as well as plant and fungal) cell. I don't see how it would be implausible to develop cell-to-cell cohesive mechanisms (which do exist in the form of structures such as tight junctions, gap junctions, desmosomes, etc.) on the basis of sharing cellular resources; such mechanisms could invariably lead to groups of cells, forming the first tissues. Large aggregations of cells would then need to "adapt" based on their location in the tissue: cells that are in constant contact with the environment might better "survive" if they have increased expression of genes that code for proteins designed to excrete cellular wastes that have accumulated in the other cells that occupy the same tissue, for instance.

*Shrug* I can't really rationalize things better than the established theories can. I'm, after all, just a student. The theories and their dependence on logical progressions make sense to me, and I recognize that they do not answer all of the questions about evolution (as they cannot account for the emergent properties in many organisms - consciousness, self-awareness, and so forth). However, in terms of having systems develop up to the level of a plant or animal on the basis of successful functioning in the environment doesn't seem to be far-fetched to me.

EDIT - If the endosymbiosis theory is of interest to any of you (the theory about the origin of mitochondria and chloroplasts), Wikipedia has a decent treatment of it.

EDIT 2 - On another note, the cell does carry out digestion and excretion; how else would it have been able to obtain the building-blocks for macromolecules and cellular structures? I like to credit the cell with a lot, but it isn't capable of spontaneously combining elementary particles into the necessary elements. Cells use a series of triggers when they encounter material that lead to it being ingested in a membrane-surrounded vesicle (a phagosome), which comes into contact with a lysosome (an orgenelle containing digestive enzymes and a low, acidic pH). Once the material is degraded, its component molecules and atoms are used in anabolic reactions. Wastes are excreted by a similar mechanism, but in reverse - degradation, packaging into a vesicle, and then budding-off at the plasma membrane to release the waste to the environment. This is also how a number of molecules like hormones and enzymes are released and, indeed, how extracellular digestion in the small intestine takes place; extracellular excretion is quite important.

 

[VideoJinx]

Wewps didn't mean to come off as mocking..

let me try to rephase what i was tryin 2 say earlier.. it came out in a jumble..



Look... according to evolution a Single Celled Organism Evolved into a "Multi-Celled Organism"

My opinion on this:
That is highly unlogical.

What is a Single Celled Organism?

A single celled organism is a Micro-Organism

microorganism
(mī´krō ōr´gnizm),
n a microscopic living organism, such as a bacterium, virus, rickettsia, yeast, or fungus. These may exist as part of the normal flora of the oral cavity without producing disease. With disturbance of the more or less balanced interrelationship among the organisms or between the organisms and host resistance, individual forms may overgrow and induce disease in the host's tissues. Those foreign to the individual may invade and produce pathologic processes.

Source:
http://medical-dictionary.thefreedictionary.com/Single-cell+organism

Single Celled Traits?

The diversity of single-celled organisms is astounding. These differences are apparent in both the structure and function of the organisms. For starters, single-celled organisms range greatly in size, from less than 1 micron (one-millionth of a meter) in diameter for the smallest bacteria, to more than 100 microns for some protozoans.


The manner in which single-celled organisms acquire food varies greatly too. Some, like the amoeba, go in search of food, crawling on pseudopods (temporary bulges in the cell membrane) toward prey that they eventually engulf and digest internally. Others, including all of the different species of algae, make their own food by harnessing the sun's energy just as plants do. Structures called chloroplasts inside the algae contain the pigment chlorophyll that allows them to use the sun's energy to make carbohydrates from carbon dioxide and water......

Read the rest here: http://www.teachersdomain.org/resources/tdc02/sci/life/stru/singlecell/index.html

What is a Multi-cellular Organism?

Describes an organism that has more than one cell, such as animals and plants.

Animals for example:

Animals contain organs that are Multi-Cellular. A good example of an organ would be the heart. The heart isn't an organism that can "live" all by itself which is why it's called an organ. It is made up of many cells with different specified funtions..that function together, allowing the heart overall to do its' function, which is to take in and push out blood for Cirulation of the animal's body. Why or even how would a Single-Celled organism "evolve" into a heart?? How would evolving into a heart benefit a single celled organism? Or even a liver, or spleen or a brain ect ect? Why would a Single cell organism evolve into any of an animal's organs?

It doesn't make sense to me.. how would it benefit by becoming a skin-cell.. etc etc...

 

[Majin_You]

It doesn't make sense to me.. how would it benefit by becoming a skin-cell.. etc etc...

The best reason I can think of as to why a multi-cellular organism would have be more resilient than a completely independent, unicellular organism is one basic notion:

If there is permanent cellular damage to, say, a paramecium's nuclear transport proteins (molecules responsible for shipping stuff into and out of the nucleus), it likely will not survive.

If a human heart cell has taken similar damage, it will die and be replaced by the division of a neighboring cell, and the organ will continue to function normally. Similarly, if certain organs are damaged in a multi-cellular organism, the organism will not immediately die. If I were to disable all of the cells in your left kidney (that's a lot of cells to begin with), you may still live. Multiple cells in your body can be severely damaged, even killed, without you even feeling a decrease in your capacity to carry on with your life. If the same amount of damage is done to a unicellular organism, there's little more to be said about it.

Damage control, as it were; the vital functions of a multi-cellular organism are not restricted to operations in a single cell, while, in protists, all vital functions are carried out in a single cell.

 

[kam!]

Why or even how would a Single-Celled organism "evolve" into a heart?? How would evolving into a heart benefit a single celled organism? Or even a liver, or spleen or a brain ect ect? Why would a Single cell organism evolve into any of an animal's organs?

It doesn't make sense to me.. how would it benefit by becoming a skin-cell.. etc etc...

Single celled organisms didn't just evolve into organs. First they (probably) started forming colonies,
several individulas sticking together to form one of the first multi-cellular organisms.
In this little cluster of cells, it is more efficient if certain cells perform certain tasks.
The outer cells may specialize into dealing with substances that the organism comes into contact with,
be it food, toxins or other organisms. Other cells in the colony perform other tasks.
Now we have a rather simple multi-cellular organism, in which some cells perform specific tasks
(which is a logical thing to do, since it saves energy). Now this organism grows more complex,
and thus the number of cells needed to perform specific tasks (e.g. digestion of food molecules) inceases.
Now there are more cells responsible for digestion, and because it is more efficient, all these cells are close together within the organism.
Now we have our very first simple tissue. Not quite yet an intestine, but a tissue (group of cells within an organism performing a special task).
If you continue this path of simple things getting more complex, you end up with bigger tissues, which at some point become big enough
to be called organs.

 

[VideoJinx]

To be more resilient?

Even that "reason" doesn't make sense to me based on this very reason. Multi-cellular organisms have organs with specified functions. A Unicellular organism cant become a Multi-celled organism without the organs***.

So it must first become an organ which would serve no benefit to itself because an organ alone would soon die. Edit*: Especially since organs depend on other organs for survival

 

[kam!]

To be more resilient?

Even that "reason" doesn't make sense to me based on this very reason. Multi-cellular organisms have organs with specified functions. A Unicellular organism cant become a Multi-celled organism without the organs***.

So it must first become an organ which would serve no benefit to itself because an organ alone would soon die. Edit*: Especially since organs depend on other organs for survival

That's where your idea of evolution is wrong it seems. Evolution didn't go straight from single-celled organisms to fish and cats and dogs.
The first mulit-cellular organisms didn't need organs at all. They probably were just a clump of 20-150 cells.
Evolutionary processes made certain cells specialize in certain tasks. Read my last post for more information.

 

[VideoJinx]

Single celled organisms didn't just evolve into organs. First they (probably) started forming colonies,
several individulas sticking together to form one of the first multi-cellular organisms.
In this little cluster of cells, it is more efficient if certain cells perform certain tasks.
The outer cells may specialize into dealing with substances that the organism comes into contact with,
be it food, toxins or other organisms. Other cells in the colony perform other tasks.
Now we have a rather simple multi-cellular organism, in which some cells perform specific tasks
(which is a logical thing to do, since it saves energy). Now this organism grows more complex,
and thus the number of cells needed to perform specific tasks (e.g. digestion of food molecules) inceases.
Now there are more cells responsible for digestion, and because it is more efficient, all these cells are close together within the organism.
Now we have our very first simple tissue. Not quite yet an intestine, but a tissue (group of cells within an organism performing a special task).
If you continue this path of simple things getting more complex, you end up with bigger tissues, which at some point become big enough
to be called organs.

Even this doens't make sense to me.. are you suggesting that Single-celled organisms had the "Intelligence" to work together with different types of Single celled organisms?

It's true IF cells work together they can become a more efficient organism. Example: Organisms today have that.

But in the presence of an evolutoinistic explanation..

WHY and HOW would a Unicellular organism attach itself to other Different Unicellular organisms...

In my opinion they wouldn't..

That's where your idea of evolution is wrong it seems. Evolution didn't go straight from single-celled organisms to fish and cats and dogs.
The first mulit-cellular organisms didn't need organs at all. They probably were just a clump of 20-150 cells.
Evolutionary processes made certain cells specialize in certain tasks. Read my last post for more information.

An organism.. by definition REQUIRES organs. Just to let u know Unicellular organisms have "organelles"

 

[kam!]

Even this doens't make sense to me.. are you suggesting that Single-celled organisms had the "Intelligence" to work together with different types of Single celled organisms?

It's true IF cells work together they can become a more efficient organism. Example: Organisms today have that.

But in the presence of an evolutoinistic explanation..

WHY and HOW would a Unicellular organism attach itself to other Different Unicellular organisms...

In my opinion they wouldn't..

It has nothing to do with intelligence or "choosing to stick together".
It's evolution, multi-cellular organisms had a slight advantage over single-cellular ones.
Multi-cellular organisms that had specialized cells were more effective (and thus were favored by natural selections).

An organism.. by definition REQUIRES organs. Just to let u know Unicellular organisms have "organelles"

Bacteria don't have organelles (in the sense of organs to an organism)

In biology, an organism (from Greek οργανισμός - organismos, from Ancient Greek όργανον - organon "organ, instrument, tool") is an individual living system (such as animal, plant, fungus or micro-organism). In at least some form, all organisms are capable of reacting to stimuli, reproduction, growth and maintenance as a stable whole (after FAO[1]). An organism may be unicellular or made up, like humans, of many billions of cells divided into specialized tissues and organs.

organism has nothing to do with having organs.

 

[Garm]

LOL:laff:

Comon man <__<


if a cell was "specialized" for digest.. it would digest and excrete right???

can you point to where our intestines excretes waste into our blood?.. or does that not happen<__<

the specialized feature of it wouldve have to completely change...

I think this is as clean cut as it gets... evolution is a fraud =o

No, your bull**** youtube videos are a fraud. Evolution is a firmly established scientific theory. Go ahead and challenge it if you like (as that is the scientific method) but at least challenge it with something other than "its unlogical" i.e. "I don't understand it properly and couldn't be arsed to read up on it (search 4 myself)." I mean, for ****'s sake, you spent half this thread decrying evolution as a failure because it doesn't explain something that it doesn't even purport to explain.

What you have to understand is that changes are gradual. It's not like suddenly a successive generation gains a digestive system. Simple multicellular organisms developed the most basic biological systems first. Complicated systems such as the digestive tract developed on top these basic systems over millions of years.

Ok, my anatomy is a bit rusty, but I'll try to provide an example. In the human central nervous system, there are several distinct regions: the spinal cord, the cerebrum, the lower brainstem, the midbrain, and the forebrain. The cerebrum (the grey, folded matter) is relatively new in comparison to the latter three parts I just mentioned. All of our higher functions are centralised in the cerebrum. For instance, the frontal lobe of the cerebrum is associated with planning, the temporal lobe with vision, and either side of central sulcus with movement and sensory functions. It's the old stuff - the midbrain, forebrain, etc. - that controls the more basic biological systems, such as sleep, autonomous heart function, reflex arcs, etc. In essence, the brainstem and its divisions are a still-functional remnant of a time when higher nervous function didn't exist.

The point that I'm trying to make with this is that the more complex systems gradually build upon older, less complex systems. Specialised cells for the digestive system don't just crop up in one generation. Maybe in basic multicellular organisms mutations might result in a few cells being responsible for the metabolism of food, and through further mutation, these cells become more numerous and more specialised.

Keep in mind that this stuff has happened over millions, even billions of years. That length of time is almost beyond the comprehension of the human mind. The sheer force of time has allowed selection to come so far.

EDIT: Majin's post, holy ****. I bow to you, sir. Guess I missed it before.
Take particular notice of this part of that post, it explains things better than I have:

Such an advantageous relationship (gaining the ability to undergo aerobic respiration for a massive ATP payoff, while sacrificing a portion of the cellular volume for "rent") is believed to have led to the modern animal (as well as plant and fungal) cell. I don't see how it would be implausible to develop cell-to-cell cohesive mechanisms (which do exist in the form of structures such as tight junctions, gap junctions, desmosomes, etc.) on the basis of sharing cellular resources; such mechanisms could invariably lead to groups of cells, forming the first tissues. Large aggregations of cells would then need to "adapt" based on their location in the tissue: cells that are in constant contact with the environment might better "survive" if they have increased expression of genes that code for proteins designed to excrete cellular wastes that have accumulated in the other cells that occupy the same tissue, for instance.

 

[VideoJinx]

over millions, even billions of years

Once upon a time??...





Look.... why would anyone assume that any part of the brain is "old" because certain parts of the brain control basic functions?

If anything.. when seeing how each part of the brain functions in a simultaneous manner, one can see how its a clear sign.. of Design.

The point that I'm trying to make with this is that the more complex systems gradually build upon older, less complex systems.

This still doesn't bring a logical answer to the question of how a Unicellular Organism would "evolve" into a multi-cellular Organism. From where I'm standing evolution doesn't WORK/FIT in this situation.. implying a likely, false theory in my opinion

 

[MC]

Once again, Intelligent Design and Evolution cannot be compared. Intelligent Design deals with how life came into existence, Evolution deals with how life came to be as it is now.

The Discovery Institute is a think tank based in Seattle, Washington, best known for its advocacy of intelligent design and its Teach the Controversy campaign to teach creationist anti-evolution beliefs in United States public high school science courses. A federal court, along with the majority of scientific organizations, including the American Association for the Advancement of Science, say the Institute has manufactured the controversy they want to teach by promoting a false perception that evolution is "a theory in crisis" by incorrectly claiming that it is the subject of wide controversy and debate within the scientific community. A federal court recently ruled that the Discovery Institute pursues "demonstrably religious, cultural, and legal missions", and the institute's manifesto, the Wedge strategy, describes a religious goal: to "reverse the stifling dominance of the materialist worldview, and to replace it with a science consonant with Christian and theistic convictions."

Source: http://en.wikipedia.org/wiki/Discovery_Institute

 

[SailorAlea]

This still doesn't bring a logical answer to the question of how a Unicellular Organism would "evolve" into a multi-cellular Organism. From where I'm standing evolution doesn't WORK/FIT in this situation.. implying a likely, false theory in my opinion

1) Evolution of Multicellularity

2) I'm going to turn the argument around on the other foot. Where's your proof that a supreme deity designed all life? Evolution has enormous amounts of evidence. Where exactly is Intelligent Design's evidence?

"Life is complicated" is not support for "Intelligent Design."
"Current scientific theories don't explain (to my satisfaction) abiogenesis" is not support for "Intelligent Design."
Biblical scripture is not support for "Intelligent Design."

Intelligent Design is well-known pseudo-science. It's creationism in disguise. It makes no testable hypotheses or predictions, which are essential to science.

It's your turn to come up with evidence, Jinx. Since you're supporting a religious notion, I have no doubt in my mind whatsoever you're going to come back with religious sources, which hold no validity in a scientific setting.

"Some guy says God said: X" is not a scientific argument. But if you're arguing evidence suggests a supreme power "designed" life, let's see it.

 

[kam!]

This still doesn't bring a logical answer to the question of how a Unicellular Organism would "evolve" into a multi-cellular Organism. From where I'm standing evolution doesn't WORK/FIT in this situation.. implying a likely, false theory in my opinion

Since I feel like you ignored some of my posts again, I'll just drop this thread.
I described it in two posts, Garm posted a version as well, and Alea posted a source I gave yesterday.
I don't know how your logic works, but evolution is one of the most logical things in biology.
There are certain basic principles, and you can apply them to any situation.