Hi everyone! I've taken on a new path in life -- understanding everything I can about science. I would be so appreciative if you would please touch upon something that you know about science. And please explain it in detail -- in layman's terms. This old gal has a dictionary, but some of those concepts are heady and sometimes I just need it spelled out for me. Thanks in advance for your participation!
As a kid who liked natural sciences, I detested botany and the whoop about photosynthesis. I have since matured to appreciate the plants' ability to harness the energy of sun light and convert that mere light energy to biological energy more efficiently than any man made system. It strikes me the most when I marvel at a fast growing ten foot tall sun flower. Those huge green leaves doing their job making oil rich seeds. Photosynthesis is my favorite scientific concept - if that's what y'were asking. And for a mind blower, Chloroplast, similar to Mitochondria, have their own DNA that is more like ancient bacterial DNA than the nucleus/chromosome DNA of a plant or animal. Moi No
[video=youtube;0uRCVyJ7-0c]https://www.youtube.com/watch?v=0uRCVyJ7-0c[/video] Decay of LD for SNPs with minor allele frequency <10%. (A, B) Real data for European Americans and East Asians shows longer range LD when the Neandertal genome has the derived allele (left) than when it has the ancestral allele (right). This is as expected due to gene flow from Neandertal, but is not expected in the absence of gene flow. In other words, the fact that LD conditional on Neandertals having the derived allele is longer than LD when Neandertal does not strongly suggests that the pattern we are observing among ascertained SNPs is reflecting the complex historical relationship between non-African modern humans and Neandertals, the signal we care about here, and not demographic events that solely involve the ancestors of non-Africans. Comparisons of DNA sequences between Neandertals and present-day humans have shown that Neandertals share more genetic variants with non-Africans than with Africans. This could be due to interbreeding between Neandertals and modern humans when the two groups met subsequent to the emergence of modern humans outside Africa. However, it could also be due to population structure that antedates the origin of Neandertal ancestors in Africa. We measure the extent of linkage disequilibrium (LD) in the genomes of present-day Europeans and find that the last gene flow from Neandertals (or their relatives) into Europeans likely occurred 37,000–86,000 years before the present (BP), and most likely 47,000–65,000 years ago. This supports the recent interbreeding hypothesis and suggests that interbreeding may have occurred when modern humans carrying Upper Paleolithic technologies encountered Neandertals as they expanded out of Africa. http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal .pgen.1002947
First, you have to know a tiny bit about what the scientific process is. The process begins like this: First you see something. Then you form a hypithesis. The you test the hypothesis. Then comes falsification, which is something I fail to understand myself, but I do know it is about finding potential errors in the testing and the results of the testing. Then you publish your testing methods and your results. All conclusions must be base on the results of the test, what those results can tell you in an accepted scientific journal. Oh, and in science a theory is a body of facts that have been observed and verified. Gravity is a theory which is about gravitational forces that affect planetary systems, but not only that. Black holes exert a lot of gravitational force. That's what separates science from religion.
I think a star is a magical thing. Energy created at the center of the star is pushing out forcing the star to expand. Gravity also created by the stars mass is pulling it in. A star is (In my mind) is the perfect example of an irresistible force and an immovable object encountering each other
Personally I find Evolution to be fascinating. Basically the combination of extreme time frames and adaptation to environment through genetic mutation producing new and unique creatures. I am particularly amazed by whale evolution, and the Idea that an ancient sea creature became a land animal that then returned to the sea. Many still have residual leg bones.
Genetics and anthropology/archeology....the human evolutionary journey, dna that links every single one of us together, we're all related, one enormous family and we all came from africa....if I hadn't changed career paths in uni thats what I would be doing today.... if i had only finished my uni degree I'd have lived my dream career....
Bernoulli's principle. As the speed of a moving fluid (liquid or gas) increases, the pressure within the fluid decreases. Using this principle an airfoil creates lift, and is one of the fundamental forces involved in flight. Air moving over the top of an airfoil moves faster (llower pressure) because of the curvature of the airfoil, while the air moving below the airfoil moves slower (higher pressure) as there is no curvature. The resultant differences in pressure areas cause the higher pressure to "push" up on the airfoil...thus generating lift.
Yeah thats a good one. I remember being enchanted by the concept at school And suddenly understanding why hoses whip around like demented snakes when they are running
The mechanics of flight are often explained, and even often taught in schools, as a consequence of Bernoulli's principle. I assume this is done since it is fairly easy to understand, however, it isn't exactly correct. There's a lot more going on that's necessary to create lift. Here is a more detailed and accurate explanation of the mechanics of flight... http://www.allstar.fiu.edu/aero/airflylvl3.htm
Aint that funny - I sometimes wonder if all the anti science people out there understand exactly how much science goes into every day things? - - - Updated - - - Well to be fair to Herkdriver - The OP did ask us to keep things pretty straight forward
Agree, that in itself is fascinating but couple that with what happens in binary star systems and large stars versus small stars when they die is even more fascinating. Without all of those different combinations producing different elements we wouldn't even be here. We are literally made up of stardust. Black holes are equally impressive as is dark matter and dark energy. Why our universe could exist inside a black hole for all we know and the black holes we observe could also be the source of big bangs for other multiverses. Its mind boggling.
Oddly enough, I dont find those things that mind boggling, possibly being exposed to such concepts most of my life may have left me jaded. However things such as Sloan's Wall put me to the point of checking out lol http://news.discovery.com/space/sloan-great-wall-galaxy-supercluster-110510.htm
Thank you...I have a degree in aviation science and over 7,500 logged flight hours...I believe I am familiar with the principles of flight. The OP asked for a laymans explanation of [A] scientific concept... I presented Bernoulli's principle of fluid mechanics as it applies to air, a fluid, moving over an airfoil. Taking it a step further...probably complicates it unnecessarily given the question asked specifically to present the explanation in non-expert terms. Bernoulli's equation p + 1/2 pV2 +pgh = constant pressure, velocity, gravity and elevation I could could have gone further and discussed Newton's 1st law, 2nd law and 3rd law of motion as well....as the principles of flight involve both Newton's laws and Bernoulli's principle. The fact remains Bernoulli's Principle helps create lift, one of the four fundamental forces acting upon an aircraft in flight. The OPs question was asked and answered.
Both mitochondrial (mtDNA) and nuclear DNA have been extracted from Neanderthal specimens and the first analysis of mitochondrial DNA (mtDNA) from Neanderthals was published in 1997. The scientists have focused mostly on Neanderthal specimens' nuclear DNA, the genetic material from the chromosomes in the nucleus of the cell that a person receives from both their mother and father. But they also examined mitochondrial DNA (mtDNA) from Neanderthals, which is passed down solely from the mother.
YOU mis edited a PM and there is a reason for the P in PM Why don't YOU tell us why we have no Neanderthal mtDNA in HumanKind today. All mtDNA today is representative of the last, "out of Africa". Must be a
Sorry Herk, I didn't mean for my post to come across as a slight toward you in any way, or to suggest that you were necessarily wrong. Even I was initially taught flight was caused by Bernoulli's principle and nothing else. You are correct in answering the OP's question as it relates to laymans terms, I was only attempting to provide additional detail for anyone who may be interested. Perhaps I should have chosen better wording - apologies.
fluid dynamics, particularly in liquids. Beyond that, H2O has some interesting qualities like it expands when it freezes instead of contracting like most things and falling water has slightly more pressure than rising water (which is why you see a lot of little water towers on top of old buildings in big cities despite people thinking they are there to collect water or whatever)
Falsification is pointing out ways that your idea could be shown to not be true. If there are no ways to do this then it's not considered very scientific. There's a famous saying in science, I forget who originally said it, "This isn't right, it's not even wrong."
