Posts Tagged → science
DNA Replication Animation
This is a clip from a PBS production called “DNA: The Secret of Life.”
It details the latest research (as of 2005) concerning the process of DNA replication.
Google search the PBS title and you can find the website which has links to many informative sites and interesting clips. This is just a segment detailing replication.
Cure for Dysentery? Camel poop
Dysentery (formerly known as flux or the bloody flux) is a disorder of the digestive system that results in severe diarrhea containing mucus and/or blood in the feces. If left untreated, dysentery can be fatal.
Dysentery is initially managed by maintaining fluid intake using oral rehydration therapy. If this treatment cannot be adequately maintained due to vomiting or the profuseness of diarrhea, hospital admission may be required for intravenous fluid replacement. Ideally, no antimicrobial therapy should be administered until microbiological microscopy and culture studies have established the specific infection involved. When laboratory services are not available, it may be necessary to administer a combination of drugs, including an amoebicidal drug to kill the parasite and an antibiotic to treat any associated bacterial infection.
Furthermore, Lewin (2001) reports that “… consumption of fresh, warm camel feces has been recommended by Bedouins as a remedy for bacterial dysentery; its efficacy (probably attributable to the antibiotic subtilisin from Bacillus subtilis) was confirmed by German soldiers in Africa during World War II.” In addition, sheep feces contain the same antibiotic as camel feces. There are numerous reports from German soldiers of the effectiveness of sheep and camel feces being effective cures for dysentery.
TMBG corrects record on what the Sun is
They Might Be Giants… but they were wrong about the Sun. At least they’re big enough to admit it!
The original: Why Does the Sun Shine? (The Sun is a Mass of Incandescent Gas)
The revision: Why Does the Sun Really Shine? (The Sun is a Miasma of Incandescent Plasma). Directed by David Cowles & Liesje Kraai. From TMBGs new DVD/CD set Here Comes Science.
Why mirrors reverse images
Richard Feynman amuses himself with an old puzzle – why do mirrors seem to switch left and right, but not top and bottom? From the BBC TV series ‘Fun To Imagine’ (1983)
What keeps a train on the tracks?
How gay sex can produce offspring
Gay sex – in beetles, at least – gives males a chance to indirectly fertilize females they may never encounter directly says NewScientist.
Homosexual copulations are common in insects, where they pose the same conundrum as in mammals: what evolutionary advantage, if any, might such apparently fruitless activity provide?
Over the years, biologists have proposed a range of explanations. Homosexual activity might, for example, help males practise for straight sex, or they might offer males a way to assert dominance over one another.
Although we don’t know why they spelled “practice” with an “s” instead of a “c”, we DO find their video of homosexual beetle porn to be…fun:
The Large Hadron
Sad news: “Black Hole Death Machine” Claims First Victim, as Teen Commits Suicide Due to Fears of the End of the Universe. Sort of a point here: “Her father… said that his daughter, Chayya, killed herself after watching doomsday predictions made on Indian news programs.” — Yeah, if I believed half of the crap the media tells me, I’d have been dangling from the garage roof years ago. Dick in hand, of course. When I go, I’m going “Hutchens style.” Live by the sword, die by the sword.
But what exactly IS the Large Hadron? besides some gigantic science fair project that I keep reading as “large hard on” every time I see it, its also an experiment to find out the secrets of the universe. woot!
PS: don’t kill yourself over it.
Why do dogs sometimes eat poop?
Well, the technical term for “poop eater” is Coprophagia and its most common in much smaller animals. Some insects consume and redigest the faeces of large animals which contain substantial amounts of semi-digested food. (Herbivore digestive systems are especially inefficient.) The most famous faeces-eating insect is the dung-beetle and the most ubiquitous is the fly.
Bigger animals too. Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft caecal pellets of partially digested food are excreted and generally consumed immediately. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the faeces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to get any nutritional value from plants.
Gorillas eat their own faeces and the faeces of other gorillas.
Hamsters eat their own droppings, which are thought to be a source of vitamins B and K, produced by bacteria in the gut. Apes have been observed eating horse faeces for the salt content. Monkeys have been observed eating elephant faeces. Coprophagia also has been observed in the naked mole rat.
But DOGS. What about DOGS…
Continue reading →
Why we can’t clone dinosaurs from mosquito blood
Scientists have argued that much of the Jurassic Park’s (both book and film) content is impossible for various reasons, most notably the suggested means of recovering dinosaur DNA from mosquitoes trapped in fossilized tree sap. While this theory is largely a plot device by Michael Crichton (the author), both novel and movie sparked debate on the feasibility of cloning dinosaurs.
Three arguments why it would not be possible to obtain dinosaurs with this process are summarized thus:
- Dinosaur DNA would be very difficult to correctly sequence without a complete, intact DNA strand for comparison. It would be unlikely to find a complete sequence because DNA is typically unstable outside living organisms (unless it is in the proper buffer).
- Any gaps in the resulting DNA sequence must be filled with dinosaur DNA; using frog DNA as the story suggests would likely produce an organism that varied from the original animal.
- In order to clone a complete DNA sequence, an oocyte from the same organism is required. Since no Mesozoic dinosaurs are alive today, this would be impossible.
Furthermore, it is likely that any prehistoric DNA obtained from a fossilized mosquito would have become contaminated with the mosquito’s own, again making it problematic to clone an ‘accurate’ and viable organism.
A theme expressed throughout the story and its sequel is that of homeothermic (warm-blooded) dinosaurs, a then-recent theory popularized by paleontologist Bob Bakker. While the cinematic adaptation of Jurassic Park used ostrich eggs as vessels to facilitate expression, the novel described “a new plastic with the characteristics of an avian eggshell.” The plastic was called ‘millipore’, invented by an eponymous company subsequently bought by InGen (Millipore Corporation is also the name of a real company that manufactures materials for use in biological sciences, although they are not known to make dinosaur eggshells).
Another note, most of the dinosaurs featured in the novel are not from the Jurassic period; they are actually from the Cretaceous period, the last period during which non-avian dinosaurs lived. However, this may be chalked up to an ignorant or naive marketing decision on InGen’s part.