h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: The Importance of Water in Biological Systems - A2429282
Author: Patron Saint of Kittens... aka Pantherlady who's an owltrons thundercat and is THE Werepanther of h2g2 - U222826

Is this good enough?

I think I might be concerned about how many existing edited entries there are about water already, Pantherlady, eg: A596450.

But its not really about water! Its abut how its used in Biology. Ok though i understand.

This would be your first entry in the edited guide, so well done for entering it into PR.

It looks quite good, but are you sure of all of the facts? Biology is not my subject, but are you sure that
1) Photosynthesis is just the splitting of water? I thought it was the conversion of carbon dioxide and water to sugars, with oxygen as a waste product, and chlorophyll as a catalyst - so it would be debatable where the oxygen comes from, and does NOT produce hydrogen (a highly inflammable gas).
2) Red cells dissolve in water? Fish live in the sea, but do not dissolve in water, and I think the situation with red blood cells is similar.

Hopefully, someone with more knowledge of biology will visit this thread in due course. I think that you have the basis of a fine entry, so do stick with it.

Hey. Well, I'm doing Biology A-level and i had to do a big thing on this.

Photosynthesis is in several stages, the light-dependent stage and the light-independednt stage. The light-dependent is where enregy from the sun is used to break down water, like i said, so that the H atoms can be used in the light-independednt stage to split CO2 down. I've onyl mentioned the part relevant to water.

As for the comment on Red Blood Cells, I see you're point, and so I am going to go away and think about how to reword it. I know what I mean to say, but cannot find the right way to state it. hmmm

Hope this has been of some help

This looks quite good, assuming all the technical biological stuff is correct. I don't know enough to make sure it's all accurate, but I shall ask my parents to read through it. Good work.

Hello there,

That's an interesting article you've got, and from an equally interesting point of view! I'd just like to make a couple of minor comments:

1. To be absolutely accurate, biological life did not evolve from water per se. The primordial soup that borne the first life forms was a thick stew of organic matter. But to be even more accurate, 'pantetheine', a key ingredient necessary for the development of life was speculated to have been created at the margins of evaporating pools of water... so yes, I suppose it indirectly paved the way for early life Sorry for nitpicking.

2. While you're right about water being involved only in the light-dependent phase of photosynthesis, I think it might be a good idea to add a footnote that you're only referring to the relevant stage, and that that's not all there is to photosynthesis, lest laypeople become confused about how water and broken-down carbon dioxide become plant food!

3. The statement 'water readily dissolves other substrates' is, I think, over-generalised, because there are some compounds our bodies use that are fat-soluble and not-water soluble.

4. 'Water is a fundamental component of blood plasma, tissue fluid and lymph and are used to dissolve...' er, it should be 'is' and not 'are'.

5. 'This is because ammonia and urea are toxic when undiluted and by diluting them, they can be recycled more easily in the Nitrogen cycle' - an interesting note: reaction between glutamine and water in the body *produces* glutamate and *ammonia*, which is then excreted in the urine.

6. Tears are saline solutions. I'd have to check to be 100% sure, but I'm pretty sure it's the salt that's actually responsible for the 'avoiding infection' bit because many pathogenic microorganisms aren't salt-tolerant unless they come from the sea to begin with.

7. You forgot an even more direct interaction between oxygen and water - oxygen dissolves in water! It's the reason why we have fish and other creatures living in it

8. 'even humans consist of around 65% water' - even more importantly, about 85% of the brain is water.

I'll have another look at it another time when I can; in the meantime, nice work

How's this coming along?

likewise finally getting time now...

Yoooo hooo?!?!?! Still working on this one?

The very first essay I had to write for my A-Level biology course, over twenty years ago, was on this very topic. I see it come up again and again in PR. This shows signs of being a re-heat of just such an essay. Now, I'm not saying that there isn't a potentially good entry here, but its questionable whether it's been done to death already, and whether the practice of warming-over previous work actually makes for good EG material. Think about it.