11

Okay so this table lists anaerobic respiration pathways and the reduction potentials they produce, as alternative pathways use either primary reduction or primary oxidation as a gateway to the Krebs cycle we can treat the EO' figures in the table as absolute values. I've made a personal call that the most accessible respiration pathways for large life forms ...


10

As said many times here and in many other places, the problem with going to space is not about going high enough (a flight from Amsterdam to Tokyo travels more linear distance than a flight from Cape Canaveral to ISS, you could cover the distance to space in 1 day with a bike and a bit of exercise), but it's more about going fast enough. Orbital velocity is ...


8

TL;DR: you can't make a space-shuttle sized thing fly like a bumblebee, because engineering isn't scale-independent. In addition to the obvious issues (eg. you'll save very little over a conventional rocket launch) the other major problem is that bees are small and light, whereas things that are considered to be surface-to-orbit cargo vehicles are very much ...


7

As for biology, this may be the wrong approach to think about it. We don't make rooms rectangular because we fit in them better, we make them that way because our stuff fits in them better. As long as you have 1-directional gravity, a flat floor and ceiling connected by vertical walls will be best for storage efficiency no matter what your organism looks ...


7

The short answer to your question is that your plants could be any colour, but that is a massive over-simplification of the processes that lead to plant colours being what they are. I'll go through some of the basics though to spell it out in more detail. Visible light is only 0.0035% of the EMR spectrum For a start, the plant colours we see today are based ...


5

The organism that was discovered has evolved a foreign system of encoding genetic information. Normally, genetic information is encoded in DNA, but this organism encodes it through some other method. Therefore, genetic engineering becomes useless because there are no genes to sequence, splice, etc. The scientists will have to figure out how to translate the ...


5

Paclitaxel is a complicated molecule. And a good example. It is made in the bark of yew trees and is a really good chemotherapeutic. https://en.wikipedia.org/wiki/Paclitaxel_total_synthesis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2901146/ Biosynthesis of the anticancer drug Taxol in Taxus (yew) species involves 19 steps from the universal ...


5

Life on Earth reproduces using nucleic acids (DNA or RNA). Thus a prerequisite for this to happen with an extraterrestrial life form is that it also used nucleic acid. On Earth bacteria are able to exchange genetic information among them, regardless of their species, by exchanging plasmides. Think of them like "macro" which serve specific scopes (i.e. ...


4

It isn't important at all. We call them the odd-toed ungulates, but really it's just a group of related animals that, for the most part, have odd numbers of toes. This tends to happen because the common ancestor of these animals placed most of its weight on one particular digit, so unless there's a reason not to its descendants tend to have the other toes ...


4

This is actually a plot point in the rather excellent series Troy Rising because there's an alien species addicted to maple syrup. So, to answer your question, let's take a look at what you're asking: Now, it is known what organism produces the desirable substance and where said organism can be found. With that information, what is to stop a well-funded ...


4

To get liquid CO2 you need above 5.1 atmospheres of pressure, and below -69°F. Note that if the pressure ever falls below this you get flashing to vapor above -109.3°F. So an organism that maintains an internal pressure to keep CO2 liquid might have to worry a lot about cuts. Once you get liquid CO2 at least some things can dissolve to some extent. This ...


4

Surface gravity is directly proportional with the radius of the planet and inversely proportional with the density of the planet. Now fire up LibreOffice Calc (or your favorite spreadsheet program), and play with the numbers. I suggest to put Earth's radius, surface area and surface gravity as 1 (because your are interested in relative values), but keep the ...


4

To answer without having to research complex non-oxygen based metabolic pathways: why not just photosynthesise? After all, you've only stipulated that atmospheric oxygen is a no-no, and a truly "oxygenless planet" sounds kinda unlikely (its the 3rd most abundant element in our solar system and the milky way as a whole). This requires a ready supply of water ...


3

Steven Dole suggested in his book Habitable Planets for Man the following gravity, mass and radius ranges for planets still maintaining a magnetosphere, plate tectonics, and a nitrogen + oxygen atmosphere. All values will be given relative to Earth. $$M = 0.4 - 2.35$$ $$R = 0.78 - 1.25$$ $$g = 0.68 - 1.5$$ Now you want a big planet, yet you do not ...


3

A planet "just far enough away to not be pulled in" to the Sun will have a surface temperature of just under 5780K. There is no solid material made of atoms at that temperature. You would have a gas giant with a carbon (not carbon dioxide, carbon), silicate, and metal vapor atmosphere, and nothing is going to be living on that. Asking "how close COULD they ...


2

Evolution would erase most of the physical differences between humanoid apes and humanoid felines. Assuming they had the same pressures and paths, which obviously we can't assume at all, but this isn't a question about super-intelligent felines. Cats are more 4 legged than apes (who tend to sit upright and use their hands) but that's something that can ...


2

Sextually Dimorphic Spiders This will cause some additional oddities in your ship design that you may or may not want, but I think it talks more to the biological element of the question you are asking. Female spiders are often much larger than male spiders. This means for a gender equal society of sextually dimorphic spiders to work together, the ship ...


2

what is to stop a well-funded and well-equipped research program from sequencing the genome of the organism and splicing the genes responsible for production of the substance into a bacterium, and then proceeding to mass-produce the substance afterwards? The world is full of useful compounds that we can't synthesise in this way. DNA is not a magic wand that ...


2

Remember as well that lots of animals have either vestigial digits or even tiny bits of subdermal bone that once were toes. Your animal could easily fall into one of those categories and still be strictly a (2N+1)-toed family member.


2

SHORT ANSWER: According to my rough calculations, a planet habitable for water based lifeforms vaguely similar to terrestrial life - not guaranteed to be habitable for humans or other lifeforms transported from Earth - could have a surface area a little more than 1.5 times that of Earth, which is rather disappointing. Some other answers also support that ...


2

We don't have a good measure for how much gravity a human being can sustain for a lifetime. We might well find that 1.1 g is too much. Or that we can easily adapt to 2g. We have a little better understanding of microgravity's effects on the human body, but almost none on long term higher gravity. Twice is probably too high, but anywhere from 1.1 to 1.5 ...


2

"EM energy" is light. I.e., photosynthesis. You might be able to get useful energy from the radio noise generated by charged particles captured in the plane's magnetosphere, but your plants would have to be pretty big to develop biological radio rectennae. And they would need very highly developed ion-pumping mechanisms to capture and save up teensy bits of ...


2

Our tastebuds are optimized to find tasty foods that give us required nutrients. Modernly, it is easy to overeat some nutrients, like fats and sugars, but those still provide dense calories (meaning lots for a relatively small amount of food). This habit of finding certain foods tasty encourages us to seek out those foods. Which when such foods were rare ...


1

It depends, but in a best case scenario, yes. Assuming alien food is not toxic in any way and does not clog human digestive system, it will just pass through it, acting as dietary fiber. But of course there is a definite potential for this food to act harmfully, for example as a low intensity carcinogen, so I personally would not recommend eating something ...


1

The planet's life-forms have gone through several stages: Natural development, natural environmental factors such as repeated ice-ages and extinction level events have produced over a significant timeline - a diverse range of species. Particularly in isolated island environments - much like Birds-of-Paradise, or Chichlid populations have developed on Earth. ...


1

my name is Predator. You look like a prey. Prepare to die. Predators are designed to be physically repulsive but they represent typical cat behaviours: hunting for sport using parts of prey to mark territory collecting trophies and gifting them short time of hunting proceeded with longer time of rest (per AvP cyclical visits to hunt) You would have hard ...


1

Whatever you want for your story. Cruel and self-centered. Dogs have masters, cats have personnel. Hunting prides. Very cooperative, with instinctive teamwork. Aloof and elegant.


1

On earth, solar irradiance strongly correlates with temperature because we get most of our energy from the sun. In order to separate these and have it make sense, you have to have significant energy input from some other source that is not the sun and is also not evenly distributed over the surface. The simplest, I think, would be geothermal. Something about ...


1

Hybrid: 2. a thing made by combining two different elements; a mixture. "the final text is a hybrid of the stage play and the film" Is it possible to make a "hybrid" creature which combines prokaryotic and eukaryotic methods of handling DNA? Or a hybrid which combines evolved fungal and algal elements? Yes - this is possible via symbiosis. Mitochondria ...


1

The alien has a complex hybridized reproductive and immune system. Using reproductive cells (or not) from the donor female or male, it uses stem cells to systematically copy the host cell(s) thousands of times for systematic evaluation. It randomly splices segments of its own DNA into the host's cell. The alien checks if the cloned organism is a viable, ...


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