Sodium Hydroxide + cobalt (II) chloride precipitate reaction
Sodium Hydroxide + cobalt (II) chloride precipitate reaction
Here’s PHD Comics with a great explanation of the HUUUUGE physics news this week.
Cell Size and Scale
The relative sizes of what cant be seen with the naked eye.
Robert Knox is the Edinburgh anatomist who, based upon the 16 bodies delivered to him by William Burke and William Hare, gave spirited dissections in surgical theaters and illustrated this anatomy book. So “involved” and gruesome was he in the dissections that when John James Audubon attended one of his lectures, he remarked:
"The sights were extremely disagreeable, many of them shocking beyond all I ever thought could be. I was glad to leave this charnel house and breathe again the salubrious atmosphere of the streets".
While Hare turned face and testified against Burke, who was eventually put to death (and publicly dissected, himself), Robert Knox was later acquitted of any involvement with the murders, and of any knowledge regarding the origin of the bodies. The public of Edinburgh disagreed with the court, and drove him out of town.
Though Knox has long been associated with the pair, and he should probably have taken more care in asking where the bodies came from, the light of history has shown that he did nothing illegal or untoward, especially in a day where cadavers were extremely difficult to legally come by. His enthusiasm for “continental” anatomy courses, where students also dissect bodies, was his downfall - so many bodies were needed that it was impossible to procure them all.
After the Burke and Hare fiasco, Scotland widened the availability of cadavers to anatomists with the Anatomy Act of 1832. Robert Knox had since left for London by that point, however, and spent the remainder of his days illustrating medical and zoological texts, performing pathological anatomy, and writing about his questionable theories on race, speciation, and anthropometry.
This copy of Robert Knox’s book resides at the Horniman Museum & Gardens in London, England.
Some claim that Evolution is just a theory, as if it were merely an opinion.
Einstein’s search for general relativity spanned eight years, 1907-1915. Some periods were quiet and some were more intense. The moments when the great transition occurred, came sometime between the late summer of 1912, when Einstein moved from Prague to Zurich, and early 1913.
Source (and context): A Peek into Einstein’s Zurich Notebook, from the absolutely advisable page of Goodies by Professor John D. Norton, (Department of History and Philosophy of Science - University of Pittsburgh), from now in my bookmarks.
Imagination alone is not enough, because the reality of nature is far more wondrous than anything we can imagine.
This adventure is made possible by generations of searchers strictly adhering to a simple set of rules: Test ideas by experiment and observation; build on those ideas that pass the test; reject the ones that fail; follow the evidence, wherever it leads; and question everything.
Accept these terms, and the cosmos is yours.
HISTORY OF MODERN SCIENCE: THE 18th CENTURY “MECHANICS”
Actually, they all seemed to be interested in just about everything.
Daniel Bernoulli (1700-1782) is best known for his work in fluid mechanics, in particular for his discovery that pressure decreases as flow speed increases – a fact that today keeps carburetors running and fixed-wing planes in the air.
Leonhard Euler (1707-1783), Swiss mathematician and physicist sometimes called “the Galileo of mathematical physics,” did ground-breaking work across many fields. He discovered Euler’s number, e, the second most important constant in physics, after pi.
He also introduced much of modern mathematical terminology and notation, for example, the notion of a mathematical function. Thus, Euler is justifiably remembered as a mathematician. However, he is also known for his work in mechanics, fluid dynamics, optics, astronomy, and music theory. [wp]
Joseph Fourier (1768-1830) was a pioneer in theories of heat and vibration. The technique he invented for this work – representing complex waves by adding together simpler waves – is now used everywhere in science and engineering.
Thomas Young (1773-1829) pioneered the “double-slit” experiment: shining a light through two narrow slits, he produced a pattern akin to the one produced by two overlapping water waves. This demonstration of the wave nature of light later became central to quantum mechanics.
Young made notable scientific contributions in the fields of vision, light, solid mechanics, energy, physiology, and language. He also advanced European understanding of ancient Egyptian hieroglyphs (notably, those on the famous Rosetta Stone). [wp]
Carl Friedrich Gauss / Gauß (1777-1855), called “the prince of mathematicians” by his contemporaries, is now best remembered for his “normal” (or Gaussian) distributions, which plot how likely things are to vary from average.
A German mathematician and physical scientist, he contributed significantly to many fields - in mathematics: number theory, algebra, statistics, analysis, differential geometry. In physics, he did work in geophysics, electrostatics, astronomy, and optics. [wp]
William Hamilton (1805-1865) reformulated Newtonian mechanics into what is now known as Hamiltonian mechanics. In doing so, he wrote the mathematical language in which modern physics, especially quantum theory, is expressed.
Sir William Rowan Hamilton was an Irish physicist, astronomer, and mathematician, who made important contributions to classical mechanics, optics, and algebra. [wp]
THE SCIENTIFIC TYPOGRAPHIES OF Dr. Prateek Lala: artistic representations of more than 50 influential physicists, cosmologists, and mathematicians – from Anaximander up to Stephen Hawking.
Images and descriptions reprinted (with revisions) from: Perimeter Institute
NEXT UP: Ohm, Faraday, Maxwell, Röntgen, Tesla
Heart surgery is an extremely difficult procedure. Even more so when the tiny anatomy of a small child is involved. When 14-month old Roland Lian Cung Bawi’s heart was failing him, his surgeon Erle Austin knew that he had to prepare meticulously for an intricate operation. Initially he consulted other surgeons, but this yielded conflicting advice. So Austin turned to 3D printing for help.
Using the facilities at the University of Louisville’s engineering school, Austin and his medical team produced a three dimensional model of little Ronald’s heart. Pediatric operations are difficult because the interior structures of a child’s organs are small and hard to see clearly. This model allowed the surgical team to come up with a precise plan to limit the amount of exploratory incisions, reduce operating time and prevent the need for follow-up operations.
Read more | Follow @policymic
Another property of life is that it contains DNA. This is something that I will definitely get into further so I will only cover the basics for now. The structure of DNA is simpler than it looks: it’s simply a chain of a sugar phosphate attached to one of four nucleotide bases which are adenine, thymine, guanine and cytosine.
The photo above shows how these molecules are arranged. The bonds between them cause them to coil into what is called a double-helix. There is so much to say about that but I don’t want to spoil anything, we can talk about it later. For now, just know that the arrangement of the nucleotide bases and the order in which they are arranged specifies specific amino acids. We talked about amino acids when we discussed the chemical uniqueness of the life.
Nonliving things don’t need DNA because nonliving things don’t reproduce. Chemical uniqueness in life is important because while a bird needs to make baby birds in order for birds to still exist, rocks don’t need to do that because they’re just rocks.
The best thing about DNA is that it it tells us the origin of life. Through comparative analysis of the DNA of one species to another, we can see variations and mutations that explain why one species is different from another. All living things have the same four nucleotide bases in them replicated thousands of times. Some may be similar, some may be different. We’ll talk about this a little later, but these variations cause different amino acids to form, which causes different proteins to develop. The collective amount of genetic information in a single organism is the genetic code.
Writing these makes me want to jump to so many different topics.
Let’s talk about metabolism. It’s one of those words that have been dragged into common language and completely misunderstood. When the average person talks about their metabolism, they are talking about their body’s ability to breakdown food and use it for energy. You may hear them talk about how slow or fast theirs is, or when yours will go to a complete halt. While that sort of talk is appropriate when discussing dieting it’s not what the word actually means.
Metabolism is actually a composite term for all of the cellular functions we undergo to stay alive. This includes breathing oxygen, repairing damaged cells, creating macromolecules and storing energy.
Specific organelles carry out different metabolic processes. Some organelles make proteins, other store them, others create complex sugars, some break them down. There are organelles that make energy and there are organelles that pick up wastes. Metabilism is wa more than the ability to break down food.
Reproduction is probably the most important trait of living things because since living things die, there wouldn’t be a way to continue life without replacing it. You wouldn’t be here reading this and I wouldn’t be here typing this if it weren’t for reproduction.
Reproducing is a way for old cells and organisms to replace themselves. Because you and I are multi-cellular, we not only reproduce sexually but asexually every time we shed skin or intestinal lining, or our blood—I mean whatever, a lot of us reproduces we can talk about it later.
Asexual reproduction is that thing you all hate—meiosis and mitosis. I’m still not sure why people dislike these things so much because they’re really basic, but I’ll cover them for you.
Sexual reproduction really doesn’t need to be explained in a general sense. Does it?
However, some of you might be surprised to learn that plants reproduce sexually as well. Sexual reproduction simply means that male and female gametes meet to create offspring.
Reproduction allows a species to pass on genetic material causing heredity and variation. Heredity is the transmission of genetic material from the parent to the offspring, while variation is the differences between one organism and another. Variation would occurs when we consider some animals have tails while others don’t, or how some children have straight hair while others have curly hair. Variation covered the differences between every individual species as well as organisms between a species. Plants and animals that reproduce asexually will make exact copies of itself, meaning there won’t be any variation between the parent and offspring, or the population within. This excludes mutations though—which is also a form of variation. I’m gonna have fun explaining all of these things.
The other cool thing about living is that you’re not composed of a uniform array of the chemicals I mentioned before. Instead, there are complex arrangements. With a rock (I keep picking on rocks because they’re boring sorry) you may have atoms of a substance and them molecules of a substance. That’s about as high as their hierarchy goes. In living things, you get more complex arrangements that surpass a simple “molecule.” There are organelles, cells, tissues, organs and organ systems that make up an organism, all made from the complex chemicals explained in the last blog.
The kind of chemistry above? Boring and predictable. If you do the same thing the exact same way every time, you get the exact same results. Life science is different. So many chemical cascades make an organism undergo changes all of the time. What you do to a cell when it isn’t saturated isn’t the same as what it would do if it were. Furthermore, a cell can do many chemical processes by itself by generating its own energy (a chemical process in and of itself) and driving other processes to take place as needed.
Remember when I did that blog on the cell membrane? (Yeah, me neither.) That alone shows the chemical complexity in living systems. Absolutely nothing else in nature is like this! That’s why biology is cooler than any other science.
Okay, so of course the chemicals found in life can be found in non-living things. There are experiments where you can create primordial soup that has these basic molecules, but cells are the smallest thing that can use these chemical functions and reproduce.
Reproduction leads us to part three…
Properties of life Part I
As an initial thought, it’s hard to define what makes something living. When we talk about movement, some may argue that a rock can move if gravity rolls it down a hill or that the ocean moves in response to the moon’s gravity. However, there are many different things that make living things unique. They are chemically different from any other substances on the planet, as the video above explains. I also want to get into even more properties that make living things different from nonliving things as a beginner into explaining the complexities of life.
For this blog, let’s go back to what I was taking about in the past paragraph: chemical uniqueness. Macromolecules are far more complex than any molecule in a nonliving organism. I will be explaining macromolecules in my own words here eventually. While macromolecules are only found in living things, they have the same bonds and follow the same rules as any other compounds in nature. There’s no magic to them, simply uniqueness. It may seem like semantics but it’s important to mention that difference when we discuss these sorts of things.
I won’t leave you hanging on my word until I get into macromolecules. Who knows when that will be? You know how iffy I am about adding these blogs. So here’s a little bit about them: there are four kinds and they are nucleic acids, carbohydrates, amino acids and lipids. They combine to make more familiar substances, DNA, sugars, proteins and fats respectively.
I need a second to complain…
There are so many diets out there that say to stay away from this or that in order to be healthy. Paleo diets or Atkins diets and their cult following is so annoying! Consider the macromolecules above. You need proteins and carbohydrates and sugars and fats in order to survive! It’s what you’re made of! So if you are dieting, keep this in mind. You shouldn’t sacrifice food in order to have a “good” diet. People in McDonald’s aren’t eating bananas or wheat bread. These aren’t the things that “make you fat.”
I feel so much better now.
Each of these macromolecules have characteristic bonds that I’m really not going to go over now, but will help explain a lot of things later. You’re just going to have to keep following and reading to get a proper explanation. Do you know how long it takes to write these blogs? Well, this is a series (this literally took ten minutes) but there are so many things I would like to cover here and no one’s reading so I have little incentive to update often.
So like, reblog, share, tell your friends to follow or whatever.
There will be more parts to the properties of life coming soon. Read them all—or the ones that interest you.