You've got more bacterial cells than human cells in you

[bumab]

Originally Posted by TeleMad

No, nutrients pass INTO the cells lining the GI tract when they are absorbed.

Obviously were argueing definitions, but for the sake of argument i'll move to the analogy to show my definition is correct.

Originally Posted by TeleMad

You're stretching the analogy there bumab.

How so?

To elaborate, imagine my fist has playdough in it, not a penny.

In the mouth, food is physcially mashed around and chemically acted upon by molocules excreted by the surfaces of the inside of the mouth.
- I can do that in my fist. I mash it around, and sweat on it. Perfect analogy.

Next, food is moved through physcial action down the esophogus towards the stomach cavity.
- I can do this as well- I can move playdough around inside my fist through muscle action. a small piece can move all over without my ever opening my hand.

In the stomach, food is again acted upon physcially and chemically.
- Easily possible in the fist. I can again mash it around, and my sweat will certainly act upon the playdough. That the sweat causes no digestion of the playdough is irrelevent- the analogy still stands.

In my intestines, nutrients are absorbed from the food and the rest is pushed towards the colon.
- While my fist doesn't really absorb things from playdough, it could- many poisons are absorbed through skin contact. Same thing!

Food exits through the anus.
- I relax my fist, the playdough comes out.

The analogy stands- you can pass inside something without passing through something. I can climb inside a car, and I can climb outside a car. I can't go through (by this definition) a car.

[The Barbarian]

That is not counting all the many, many mitochondria in every one of our cells, each of which is an endosymbiotic bacterium, replicating with it's own bacterial DNA.

[TeleMad]

Originally Posted by bumab

Let's not get personal.

Personal? I simply pointed out that your statements were incoherent. They were. That's your fault, not mine. And it's not personal , it's factual.

bumab: I dropped the cellular structure argument.

You should have never brought it up.

bubmab: Cohert arguments have been presented. Tell me how closing a penny in a fist, then opening it, is different from food passing into and out of the body. Both are voluntary muscle movements that open passages up. Neither move physcially "through" anything.

Try lookin at a better analogy, like the one I gave with a person driving through a tunnel. To do that, one only needs to drive from the opening on one side to the opening on the other side, traveling through the interior in the process. No penetration of the bounding wall is needed: travel through the interior passageway counts as passing through.

Hence, foodstuff that don't get absorbed do pass through the GI tract. And since the GI tract is part of the body, the food also passes through the body.

[TeleMad]

Originally Posted by The Barbarian

That is not counting all the many, many mitochondria in every one of our cells, each of which is an endosymbiotic bacterium, replicating with it's own bacterial DNA.

Mitochondria are not bacteria. They evolved from bacteria. Two different things.

[bumab]

Originally Posted by TeleMad

No penetration of the bounding wall is needed: travel through the interior passageway counts as passing through.

That calls for a defense as well.

When we talk about high energy particles passing "through" something, it's because they really go through it- tissue and all. They don't look for a tunnel.

A tunnel is a feature of the wall. You go through a tunnel, you don't go through a wall.

[TeleMad]

Originally Posted by bumab

That calls for a defense as well.

When we talk about high energy particles passing "through" something, it's because they really go through it- tissue and all. They don't look for a tunnel.

So what? My usage of "pass through" is still quite correct.

Actually, both of my usages of the phrase are correct. If someone drives a device through your skin and tissue to reach a glob of chyme in your duodenum, then that device has passed through your small intestine. On the other hand, if earlier some chyme traveled all the way from the pyloric sphincter to the illeoceccal valve by means of normal muscular contractions of the GI tract, then it passed through your small intestine. Both usages are correct, and context indicates which is being used.

[The Barbarian]

Mitochondria are not bacteria. They evolved from bacteria. Two different things.

Ah, a splitter. They are obligate endosymbiotic bacteria in the same way that humans are fish. We just don't like to think of them that way.

[Biochemist]

Originally Posted by The Barbarian

..They are obligate endosymbiotic bacteria in the same way that humans are fish. ...

This is still a postulate, even though commonly held. The fact that mitochondria (and chloroplasts for that matter) have some characteristics similar to bacteria does not prove anything other than a clever infrastructure is commonly used. So are bones and eyes. We don't see any bacteria that look like mitochondria. We can also postulate that they became extinct. We can postulate, we can postulate, we can postulate.......

[bumab]

It's a semantical issue (just like the "through" argument i've been having for fun).

Obligate symbiote or organelle?

[The Barbarian]

This is still a postulate, even though commonly held.

It's an inference from evidence. Quite a lot of evidence.

The fact that mitochondria (and chloroplasts for that matter) have some characteristics similar to bacteria does not prove anything other than a clever infrastructure is commonly used.

It seems a little hard to see why a circular bacterial chromosome would be required. Or why the code is very similar to that of bacteria and Archaea.

And DNA analysis shows that in a comparison of chloroplasts, cyanobacteria, and eukaryotes, eukaryotes are the outgroup.

These organelles are similar in size and shape to bacteria, and their ribosomes are more like those of prokaryotes than eukaryotes.

I would say that was compelling.