But then humans are very good at acquiring tastes and then celebrating them.

Many spices are supposed by nature to be poisons or at least "leave me alone because I taste disgusting" deterrents, but we caught onto the taste and even put them in our food intentionally.

Which is why small children typically don't like spicy food.

If you want to be fundamental about it, the only food that actually wants to be eaten is fruit and nuts, because that serves the spreading of the seeds.

Leaves, stalks and roots do not want to be eaten. Even less so anything that crawls, walks or flies.

Well, that's what I thought. If it doesn't have a seed or pit it must contain something to deter from being eaten. Often causing allergies, imho. Storage proteins often cause allergies.

As per spices - I think it was on some Brit TV last night, the spice shop and history of "purity" of spices, the spectrum analysis of how real the ingredients are (they get faked, they talked of fake curcuma, safron, etc.). Makes sense since it used to be a currency. In my humble imagination though, if it was currency, it couldn't have been only for our flakey tongues that are trainable, that aquire (or not), etc. But because they are healthy. They boost metabolism, curb depression I read somewhere, libido as well if I am not mistaken and preserve foods. Like chocolate - people get hooked because those endorphines are healthy.

Kids don't like veggies, it is because they are low on proteins as mentioned earlier. But also, veggies are"grown up foods" for them. Kids I know loved spices until they realized that they are "grown up foods". Then all went out the window and "kid food" won. For a while.

Ok, not a bright Q today but something I don't really want to google - I just ate a date (medjool), can I plant it?

We regularly plant citrus seeds to get a "surprise" when we forget about planting it.

__________________
"L'homme ne peut pas remplacer son coeur avec sa tete, ni sa tete avec ses mains." J.H. Pestalozzi

“The only difference between a rut and a grave is a matter of depth.” S.P. Cadman

"Imagination is more important than knowledge." A. Einstein

I few years ago I read about this topic - a very old date seed (2000 yo) was discovered at an Israeli archeological site. It was planted and it sprouted. They were hoping for a female seed, but it was male - a healthy tree grew, and they used it to pollinate female trees.

https://www.smithsonianmag.com/smart...ced-180954746/

https://www.theatlantic.com/science/...-seeds/606079/

There is hope for palm trees! Awesome. Dates must be rrally healthy...no storage proteins and made to last millenia.

My daughter is studying biochemistry at undergraduate level. This is the question we're stuck on from her text book.

Suppose that you are climbing a high mountain and the oxygen partial pressure in the air is reduced to 75 torr. Estimate the percentage of the oxygen carrying capacity that will be utilized, assuming that the pH of both tissues and lungs is 7.4 and that the oxygen concentration in the tissues is 20 torr.

The answer is 62.7% - that's at the back of the book. But we're trying to figure out exactly how that is calculated. A 7.4pH indicates that the pH is normal, so no need to adjust for that.

Can the answer be calculated from the 20 torr partial pressure in the tissues, and the 75 torr partial pressure in the air? If not, what other information do I need? Maybe a standard conversion or assumption - like I'm starting the climb at sea level? (I can't work out how to do it from the text before the exercises ).

__________________
Down with racism. Long live miscegenation!

Something to do with the Bohr effect, perhaps?
https://en.wikipedia.org/wiki/Bohr_effect

She figured it out. What she needed to take into consideration were:
Effective oxygen binding sites, or Hill Coefficient, of haemoglobin is 2.8.
From the Hill Plot Equation for 75 Torr, we get 95.1% of O2 binds
For 20 Torr we get 32.4%

Subtract one from t'other = 62.7%

Easy, innit.

TL;DR - the additional information we needed was really just the 2.8. And that we needed to use the Hill Plot Equation.

But anyway - thanks to all who took the time to read it.

I can't believe I got through first year biochemistry!

Or maybe those formulas and coefficients were invented after I graduated...

This was her first biochemistry course - she actually studying Pharmaceutical Engineering. I helped my wife with her biochemistry degree a few decades ago. I'm sure it was easier!

Something that I've thought about for a while. When you think about our programmed symmetry and the way it is at birth or before (say just a potential) - arms, feet, eyes, kidneys..Is anyone calculating the progressive asymmetry, as the life goes? What does it depend on? And, is the symmetry so real when it's only given as a potential. I mean anything in nature will probably have a similar principle. But I was thinking about human body/function specifically and why science would actually care. Is it part of medicine/biology or math?

There is “fluctuating asymmetry” which people attribute to developmental noise or stress.

And there is age related asymmetry of the face, where the asymmetry of the lower two thirds of the face are most pronounced as we age. Of course, that’s where the facial features are.

And then there’s brain asymmetry, as discussed here: https://www.sciencedirect.com/scienc...49763402000684

I’ve not seen much about functional asymmetry. Breast cancer is about 5-10% more likely in the left side, although it might be due to breast feeding more on the right being protective, or handedness. But I don’t know about things like unilateral kidney failure or lung disease. Unilateral joint replacements, and also having one eye much worse than the other.

From about 18 to 40, my right eye was nearsighted, left eye not. In my 40’s, left eye caught up with right. Now, as I develop presbyopia (near sightedness related to age), my distance vision improves.

Weird and interesting.

I get the individual manifestations, yeah. It's more post-effect data collection, though.

I am wondering how probable symmetry gets considered, before it manifests - in such a hard to predict environment where some symmetry gets to be expected but so...individually. I bet geneticians or evol biologists band with math. I also think that it is really not about symmetry but it has to help with data. It must be explored when calculating how, when and what gets affected in development. Why body - coz it's largely predictable and we know it. The universe will provide different models, so. More theoretical. Body is here and as you said, we live the asymm/symm difference. There must be a simple principle, which is the same for a leaf and for an eye. It also is quite...Darwinian, desirable. That's another thing. Universe isn't.

__________________
"L'homme ne peut pas remplacer son coeur avec sa tete, ni sa tete avec ses mains." J.H. Pestalozzi

“The only difference between a rut and a grave is a matter of depth.” S.P. Cadman

"Imagination is more important than knowledge." A. Einstein

Well, conventions of beauty pretty much rely on symmetry. More symmetrical partners are probably more successful at reproduction and passing on more symmetrical phenotypes. I suspect this applies to non humans too...and it;s interesting to consider whether symmetry provides more robust functioning.

Even Jane Austen noticed asymmetry as a detriment to beauty in Pride and Prejudice.

As for the data...well individual manifestations are summed up across samples, populations, although you may mean something else.

Still room for improvement, Dr. Who has two hearts.

I think symmetry is meant to provide functioning, sure. The aesthetics too. But I am wondering about this potential vs reality, since nature being economical, there is limit and it must be exact. So it is set to some point and then veers off, in a unique way. The uniqueness also to a point. So who calculates that, probably for medical reasons (disease manifestation, therapy costs, or whatever)..Or is it too random? I don't think it is.

In terms of dna, two symmetrical partners aren't too logical. I'd say we enter diversity for a reason.

Symmetry is a big deal in physics. There are 2 major "branches" or meanings of symmetry. One is the traditional physics symmetry understanding, that describes a system's property which remains unchanged after a given transformation (e.g. Lorenz symmetry in regards to conservation of energy or momentum, or discrete symmetry in regards to charge or time parity). The other is the layman's understanding of symmetry, when applicable to the Standard Model (somehow covered by the so-called Suppersymmetry): this states (in simple terms) that all bosons or fermions have a "partner" particle in the other group.

Thanks. I guess the symmetry in bio development is interesting to me because it's not theoretical and there are other aspects
- desirability, economical point, sustainability, self repair, etc. I don't think you can just take the numbers and put them into teoretical physics formula? Every cell has it. There seems to be an independent principle, that living world differs from the world that isn't alive. It will probably be explored by science of gmo.

...it is impossible to be perfect symmetrically, if we will be, then will get in the resonance which theoretically will make as immortals...as you now mathematically everything is imperfect around us, to prevent us get in the state of resonance...then we live on n-harmonics of the universe at the moment, if to believe in Bing-Bang we are now in the last descending harmonics, after which everything will disappear in nothing and will explode after in another Bing-Bang...

I am a shower guy, but I have a bath and backside related question! So people who take bath, aren't they really in water that is contaminated by water that is touching their asshole and circulating on to their face and body? Irrespective of how good you wipe your ass?

The Exception would be if you take a full soap shower and then have a bath.

Yeah, I was surprised at the lack of toilet humor in this thread today!

Considering what you have in your guts and the fraction of it on your butt, you are taking a bath in homeopathic concentration of your own gut flora. Which is probably harmless, we are built to resist. Girls may have to be more careful, perhaps.